With approximately 250,000 items of sexual assault evidence mired in three- to 12-month backlogs as they await analysis in U.S. forensic laboratories, there is an alarming nationwide need for a time-efficient way to get this work done, according to a University of Virginia forensic researcher.
Jessica Voorhees Norris, a Ph.D. candidate in forensic chemistry at U.Va., has found a better way. She has developed a method for handling rape kit evidence that reduces part of the DNA analysis time from 24 hours to as little as 30 to 45 minutes and improves the sperm cell recovery rate by 100 percent. If her method was to be adopted by forensic labs – and the results accepted by courts – the backlog could potentially be reduced within months.
"There is an overwhelming demand for DNA analysis of sexual assault evidence, but laboratories have neither the funding nor the manpower to handle the caseload in a timely manner," Norris said. "Juries have come to expect DNA evidence in sexual assault cases, but forensic labs are not able to perform in a timely and efficient manner due to limitations in the currently used technologies."
Norris has spent much of her career working in laboratories and long ago realized that new methodologies would be needed to keep up with the growing accumulation of unanalyzed samples. She has devoted her doctoral research to developing more effective and time-efficient methods.
When a woman is sexually assaulted and comes forward to the police, a sample is taken from the vagina with a cotton swab, which is then sent to a forensic lab. In high-profile cases, the analysis is usually performed immediately, though overnight incubation is required to achieve a result.
In most routine cases, though, the sample is put into storage, sometimes for as long as a year, before it finally reaches its turn in the cycle to be analyzed or when the case approaches a court date. The sample may degrade during the waiting period, resulting in a compromised finding.
Lab technicians must perform a number of steps to get their results. First, female and male cells must be removed from the swab with a special detergent. DNA from the vast number of epithelial cells from the victim's vagina must be separated from the far fewer sperm cells from the perpetrator. To do this, cells must sit overnight in an enzyme that bursts open the relatively fragile female cells to release their DNA for analysis. After the female DNA is removed, the highly durable sperm cells are burst open using stronger reagents. Once the DNA is extracted, profiles, in effect, are generated for both the victim and the attacker. It is a time-consuming process, one that has been in use for more than two decades.
Later, if a possible perpetrator is arrested, a sample taken from his mouth is analyzed to determine if there is a match with the sperm DNA that was removed from the victim.
Norris' method streamlines the method for separating the male and female DNA fractions, eliminating the need for the overnight incubation while doubling the recovery of sperm cells.
"This new process works extraordinarily well and could be implemented in forensic labs today," Norris said. "Unfortunately, getting labs to adopt a new protocol and getting legal systems to accept a new technology may take several years. In the meantime, the backlog of unanalyzed samples will continue to grow."
Norris noted that forensic science is not simply about proving guilt.
"Forensic science is about finding the truth in a timely manner," she said. "It is about using science to identify the guilty and exonerate the innocent."
Norris presented her findings at a recent meeting of the American Academy of Forensic Science. She will receive her Ph.D. in May this year and hopes to work as a scientist in a state- or federally funded forensics lab. She conducted her research in the lab of U.Va. chemistry professor James Landers.
Wednesday, 21 May 2008
Crime Scene Investigations: Gunshot Residue Analysis On A Single Gunpowder Particle
Scientists in Texas are reporting development of an highly dependable, rapid, and inexpensive new method for identifying the presence of gunshot residue (GSR). The test fills a GSR-detection gap that results from wider use of "green" -- lead free -- ammunition
It requires only a single speck of GSR smaller than the period at the end of this sentence and could boost the accuracy of one of the most widely used tests employed at crime scenes involving gunplay.
In a poster presented at the 235th national meeting of the American Chemical Society, graduate student Garrett Lee Burleson and his advisor, chemist Jorn Chi Chung Yu, Ph.D., of Sam Houston State University in Huntsville, described their new method. It extracts almost all components of gunpowder residue from particles about 15 times smaller than the width of a human hair, without the use of chemical reagents. After extraction, gas chromatography coupled with a nitrogen phosphorus detector is used to separate and identify the analytes.
"Gunshot residue tests are done in almost every case where a shooting has taken place," Burleson said. "The main focus of our research is to develop a method that will help credibility of gunshot residue evidence in court. You can get results with this test in 30 to 40 minutes with the new test. In addition you only need small amounts of evidence to run the test."
Many of the current methods are susceptible to outside interferences that can produce false positive or false negative results. For example, most tests require the presence of lead for a valid reading, including two of the three mainstays of residue analysis -- the sodium rhodizonate test and scanning electron microscopy with energy dispersive x-ray detection.
But Burleson points out that lead is disappearing from ammunition. That potentially toxic metal poses environmental hazards at outdoor firing ranges, where it can leach into groundwater. In response, manufacturers have begun to create safer, environmentally friendly ammunition out of other metals, such as zinc and aluminum alloys.
This recent trend toward lead-free ammunition, Burleson said, has decreased reliability of gun shot residue analysis and created the need for smarter tests to identify more diverse components of residue in gunpowder, including elements like stabilizers and plasticizers, which are added in the powder during the manufacturing process for safety reasons.
"When a gun fires, the gunpowder explodes, producing gases at enormous pressure that propels the bullet out of the barrel of the firearm," explained Burleson, a graduate student in the Master of Science in Forensic Science Program at Sam Houston State University. "Some of the residue from that explosion is deposited on the hands of the shooter and the clothing of the victim." Burleson's new test, which uses a technology called solid phase micro-extraction combined with gas chromatography, focuses on chemical compounds present in that ejected material. "When you have a residue particle, no matter how small, it's going to contain signatures of every element in that powder."
These signatures offer a wider range of detection possibilities compared to traditional methods, he said. Using an alternative method with a scanning electron microscope, for example, a forensic examiner would perform a search for lead, passing up numerous powder constituents in the analysis. "You would just look for the one little piece of metal that might be there, so the analysis could take hours," Burleson said.
"If you're looking for powder, however, there's a lot more of it. You're getting more of the residue to analyze. It makes it a much more efficient method of detection." For example, a distinctive combination of certain chemicals, such as diphenylamine, ethyl centralite and nitrodiphenylamine, is typically found only in explosive mixtures and therefore allows for a simple analysis of gunplay at a crime scene.
In contrast, another traditional test for finding gunshot residue, the modified Griess test, often fails because it lacks such specificity. Its analysis is based on the detection of Nitrogen-based compounds called nitrites, which are gunpowder byproducts. But these compounds are also found elsewhere, leading to possible ambiguity in testing.
"Many chemical cleaners -- anything that can be used to take off motor oil or freight dust -- will test positive for gunshot residue using the Griess test," Burleson said.
That would make the reading a false positive, which opens the door in court cases for reasonable doubt and possibly incarcerating an innocent person. "The worst thing you can possibly say is, 'There's a chance I'm wrong.' Our preliminary results indicate you can determine the presence of gunshot residue with a high level of confidence."
More efficient testing also would reduce the need for extraneous tests that require time and money while draining resources from a criminal justice system that cannot afford it, Burleson said.
The research was funded by the College of Criminal Justice and Department of Chemistry at Sam Houston State University.
Burleson's test could be used as a preliminary or confirmatory one. "As far as a stand-alone test, it's an excellent, reliable and cheap test to do," he said. "But for the sake of clarity and thoroughness, examiners will usually run multiple tests, such as the sodium rhodizonate test at the crime scene, and they could then confirm the findings with my method."
It requires only a single speck of GSR smaller than the period at the end of this sentence and could boost the accuracy of one of the most widely used tests employed at crime scenes involving gunplay.
In a poster presented at the 235th national meeting of the American Chemical Society, graduate student Garrett Lee Burleson and his advisor, chemist Jorn Chi Chung Yu, Ph.D., of Sam Houston State University in Huntsville, described their new method. It extracts almost all components of gunpowder residue from particles about 15 times smaller than the width of a human hair, without the use of chemical reagents. After extraction, gas chromatography coupled with a nitrogen phosphorus detector is used to separate and identify the analytes.
"Gunshot residue tests are done in almost every case where a shooting has taken place," Burleson said. "The main focus of our research is to develop a method that will help credibility of gunshot residue evidence in court. You can get results with this test in 30 to 40 minutes with the new test. In addition you only need small amounts of evidence to run the test."
Many of the current methods are susceptible to outside interferences that can produce false positive or false negative results. For example, most tests require the presence of lead for a valid reading, including two of the three mainstays of residue analysis -- the sodium rhodizonate test and scanning electron microscopy with energy dispersive x-ray detection.
But Burleson points out that lead is disappearing from ammunition. That potentially toxic metal poses environmental hazards at outdoor firing ranges, where it can leach into groundwater. In response, manufacturers have begun to create safer, environmentally friendly ammunition out of other metals, such as zinc and aluminum alloys.
This recent trend toward lead-free ammunition, Burleson said, has decreased reliability of gun shot residue analysis and created the need for smarter tests to identify more diverse components of residue in gunpowder, including elements like stabilizers and plasticizers, which are added in the powder during the manufacturing process for safety reasons.
"When a gun fires, the gunpowder explodes, producing gases at enormous pressure that propels the bullet out of the barrel of the firearm," explained Burleson, a graduate student in the Master of Science in Forensic Science Program at Sam Houston State University. "Some of the residue from that explosion is deposited on the hands of the shooter and the clothing of the victim." Burleson's new test, which uses a technology called solid phase micro-extraction combined with gas chromatography, focuses on chemical compounds present in that ejected material. "When you have a residue particle, no matter how small, it's going to contain signatures of every element in that powder."
These signatures offer a wider range of detection possibilities compared to traditional methods, he said. Using an alternative method with a scanning electron microscope, for example, a forensic examiner would perform a search for lead, passing up numerous powder constituents in the analysis. "You would just look for the one little piece of metal that might be there, so the analysis could take hours," Burleson said.
"If you're looking for powder, however, there's a lot more of it. You're getting more of the residue to analyze. It makes it a much more efficient method of detection." For example, a distinctive combination of certain chemicals, such as diphenylamine, ethyl centralite and nitrodiphenylamine, is typically found only in explosive mixtures and therefore allows for a simple analysis of gunplay at a crime scene.
In contrast, another traditional test for finding gunshot residue, the modified Griess test, often fails because it lacks such specificity. Its analysis is based on the detection of Nitrogen-based compounds called nitrites, which are gunpowder byproducts. But these compounds are also found elsewhere, leading to possible ambiguity in testing.
"Many chemical cleaners -- anything that can be used to take off motor oil or freight dust -- will test positive for gunshot residue using the Griess test," Burleson said.
That would make the reading a false positive, which opens the door in court cases for reasonable doubt and possibly incarcerating an innocent person. "The worst thing you can possibly say is, 'There's a chance I'm wrong.' Our preliminary results indicate you can determine the presence of gunshot residue with a high level of confidence."
More efficient testing also would reduce the need for extraneous tests that require time and money while draining resources from a criminal justice system that cannot afford it, Burleson said.
The research was funded by the College of Criminal Justice and Department of Chemistry at Sam Houston State University.
Burleson's test could be used as a preliminary or confirmatory one. "As far as a stand-alone test, it's an excellent, reliable and cheap test to do," he said. "But for the sake of clarity and thoroughness, examiners will usually run multiple tests, such as the sodium rhodizonate test at the crime scene, and they could then confirm the findings with my method."
3-D Images -- Cordless And Any Time
Securing evidence at the scene of a crime, measuring faces for medical applications, taking samples during production – three-dimensional images are in demand everywhere. A handy cordless device now en-ables such images to be prepared rapidly anywhere
The car tires have left deep tracks in the muddy forest floor at the scene of the crime. The forensic experts make a plaster cast of the print, so that it can later be compared with the tire profiles of suspects’ cars. There will soon be an easier way of doing it: The police officers will only need to pick up a 3-D sensor, press a button as on a camera, and a few seconds later they will see a three-dimensional image of the tire track on their laptop computer.
The sensor is no larger than a shoebox and weighs only about a kilogram – which means it is easy to handle even on outdoor missions such as in the forest. No cable drums are needed: The sensor radios the data to the computer via WLAN, and draws its power from batteries.
The sensor was developed at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena. “It consists of two cameras with a projector in the center,” says IOF head of department Dr. Gunther Notni. “The two cameras provide a three-dimensional view, rather like two eyes. The projector casts a pattern of stripes on the objects. The geometry of the measured object can be deduced from the deformation of the stripes.”
This type of stripe projection is already an established method. What is new about the measuring device named ‘Kolibri CORDLESS’ are its measuring speed, size, weight, and cordless operation. For comparison, conventional devices of this type weigh about four or five times as much and are more than twice the size, or roughly 50 centimeters long. “The reason it can be so much smaller is because of the projector, which produces light with light-emitting diodes instead of the usual halogen lamps,” says Notni. This poses an additional challenge, as the LEDs shine in all directions. To ensure that the image is nevertheless bright enough, the light has to be collected with special micro-optics in such a way that it impacts on the lens.
There are multiple applications: “Patients who snore often need a breathing mask when they sleep. To ensure that the mask is not too tight, it has to be specially made for each patient. Our system enables the doctor to scan the patient’s face in just a few seconds and have the breathing mask made to match these data,” says the researcher. Notni believes that the most important application is for quality assurance in production processes. The portable device also makes it possible to measure installed components and zones that are difficult to access, such as the position of foot pedals inside a car. The researchers will be presenting their development at the Control trade fair in Stuttgart on April 21 through 25 (Hall 1, Stand 1520).
The car tires have left deep tracks in the muddy forest floor at the scene of the crime. The forensic experts make a plaster cast of the print, so that it can later be compared with the tire profiles of suspects’ cars. There will soon be an easier way of doing it: The police officers will only need to pick up a 3-D sensor, press a button as on a camera, and a few seconds later they will see a three-dimensional image of the tire track on their laptop computer.
The sensor is no larger than a shoebox and weighs only about a kilogram – which means it is easy to handle even on outdoor missions such as in the forest. No cable drums are needed: The sensor radios the data to the computer via WLAN, and draws its power from batteries.
The sensor was developed at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena. “It consists of two cameras with a projector in the center,” says IOF head of department Dr. Gunther Notni. “The two cameras provide a three-dimensional view, rather like two eyes. The projector casts a pattern of stripes on the objects. The geometry of the measured object can be deduced from the deformation of the stripes.”
This type of stripe projection is already an established method. What is new about the measuring device named ‘Kolibri CORDLESS’ are its measuring speed, size, weight, and cordless operation. For comparison, conventional devices of this type weigh about four or five times as much and are more than twice the size, or roughly 50 centimeters long. “The reason it can be so much smaller is because of the projector, which produces light with light-emitting diodes instead of the usual halogen lamps,” says Notni. This poses an additional challenge, as the LEDs shine in all directions. To ensure that the image is nevertheless bright enough, the light has to be collected with special micro-optics in such a way that it impacts on the lens.
There are multiple applications: “Patients who snore often need a breathing mask when they sleep. To ensure that the mask is not too tight, it has to be specially made for each patient. Our system enables the doctor to scan the patient’s face in just a few seconds and have the breathing mask made to match these data,” says the researcher. Notni believes that the most important application is for quality assurance in production processes. The portable device also makes it possible to measure installed components and zones that are difficult to access, such as the position of foot pedals inside a car. The researchers will be presenting their development at the Control trade fair in Stuttgart on April 21 through 25 (Hall 1, Stand 1520).
Illinois DNA funds misused
Funds earmarked to train forensic scientists and to clear a backlog of untested DNA were improperly steered to a company overseen by the head of the Illinois State Police Crime Lab, according to reports.
A report by the state inspector general's office said an investigation found the former commander, Michael Sheppo, and others in the department retaliated against two state police training coordinators after they protested the award of a nearly $800,000 contract to two companies Sheppo headed, the Chicago Tribune reported.
The report, which hadn't been publicly released, was obtained by the two training coordinators who are suing Sheppo and other state officials in federal court.
A report by the state inspector general's office said an investigation found the former commander, Michael Sheppo, and others in the department retaliated against two state police training coordinators after they protested the award of a nearly $800,000 contract to two companies Sheppo headed, the Chicago Tribune reported.
The report, which hadn't been publicly released, was obtained by the two training coordinators who are suing Sheppo and other state officials in federal court.
Detroit Police Suspend Firearms Testing
DETROIT (AP) - The Detroit Police Department has suspended all firearms investigations conducted by its crime lab and ordered it to undergo an independent audit. Wayne County Prosecutor Kym Worthy also has ordered an audit of all of her office's files that resulted in a trial or a guilty plea that relied upon the crime lab's findings. Worthy says a defense attorney notified her two weeks ago about "significant discrepancies" in firearm evidence reviewed by the crime lab in two homicide cases and several other cases. She says that in one case, the crime lab concluded that more than 40 fired bullet casings came from a single weapon but subsequent tests showed they came from at least two different guns. ©2008 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.FROM DETROIT POLICEApproximately two weeks ago a defense attorney brought information to Wayne County Prosecutor Kym L. Worthy that uncovered significant discrepancies in firearm evidence reviewed by the Detroit Police Department Crime Laboratory in two homicide cases and several other cases. In one homicide case the defense attorney hired an independent expert to examine evidence that was reviewed by DPD firearms examiners that concluded the fired casings came from a single weapon. The defense expert concluded that there were 24 fired casings from one weapon, 17 fired casings from another weapon, and 1 piece of fired evidence that could not be identified. Prosecutor Worthy immediately sent the evidence for evaluation by an independent expert. Late in the day on April 23,2008 the Wayne County Prosecutor’s Office received information from the independent laboratory that confirmed that the findings of the defense expert. Prosecutor Worthy then informed Chief Ella Bully Cummings of this problem.On Thursday, April 24, 2008 Prosecutor Worthy instructed her staff to conduct an audit of all Wayne County Prosecutor’s Office files that resulted in a trial, or a guilty plea which relied upon findings from DPD firearm examiners. The audit will go back for one year. All and the defense attorneys on these files will be contacted and after consultation any fired evidence in question will be submitted for re-examination. The Detroit Police Department has suspended operations of the Firearm Section and has ordered and independent audit.“This a serious matter, but extremely necessary to protect the intergrity of our convictions, past, present and future,” said Prosecutor Worthy. We will also be re-evaluating any firearms evidence in our upcoming trials.
Microstamping Guns Feasible but Flawed, Study Finds
New technology to link cartridge cases to guns by engraving microscopic codes on the firing pin is feasible, but does not work well for all guns and ammunition tested in a pilot study by researchers from the forensic science program at UC Davis. More testing in a wider range of firearms is needed to determine the costs and feasibility of a statewide program of microstamping, as called for by proposed state legislation, the researchers said.
The technology developed by ID Dynamics of Londonderry, N.H., uses a laser to cut a pattern or code into the head of a firing pin. The method is similar to that used to engrave codes on computer chips. When the trigger is pulled, the firing pin hits the cartridge case or primer and stamps the code onto it. In principle, the spent cartridge can then be matched to a specific gun.
If successfully implemented, microstamping would be one additional piece of evidence for investigators to gather in building a criminal case, said Fred Tulleners, director of the forensics program at UC Davis. Tulleners was formerly director of the California Department of Justice crime lab in Sacramento, as well as the Sacramento and Santa Rosa county crime labs.
UC Davis graduate student Michael Beddow tested firing pins from six different brands of semi-automatic handguns, two semi-automatic rifles and a shotgun. The firing pins were engraved with three different types of code: a letter/number code on the face of the firing pin; a pattern of dots or gears around the pin; and a radial bar code down the side of the pin.
To test the effects of repeated firing, Beddow fitted engraved firing pins into six Smith and Wesson .40-caliber handguns that were issued to California Highway Patrol cadets for use in weapons training. After firing about 2,500 rounds, the letter/number codes on the face of the firing pins were still legible with some signs of wear. But the bar codes and dot codes around the edge of the pins were badly worn.
"They were hammered flat," Beddow said.
Tests on other guns, including .22, .380 and .40-caliber handguns, two semi-automatic rifles and a pump-action shotgun, showed a wide range of results depending on the weapon, the ammunition used and the type of code examined, Beddow found. Generally, the letter/number codes on the face of the firing pin and the gear codes transferred well to cartridge cases, but the bar codes on the sides of the firing pin performed more poorly. Microstamping worked particularly poorly for the one rimfire handgun tested.
The researchers did not have access to information allowing them to read the bar- or gear-codes, and so could not determine if these remained legible enough to be useful.
Codes engraved on the face of the firing pin could easily be removed with household tools, Beddow found.
The researchers estimated that setting up a facility to engrave the firing pins of every handgun sold in California would cost about $8 per firing pin in the first year, falling to under $2 per firing pin in subsequent years, Tulleners said.
Tulleners said that a larger test of about 3,000 firing pins, from a wider range of guns, would allow for a more "real-world" test of the technology. About 650 brands of handguns are sold in California, compared with the nine tested, Beddow estimated in the study. A bigger study would also help show how useful this technology might be in detecting and preventing crime.
The study was commissioned by the California Policy Research Center at the request of the California Legislature.
"We want to make sure that the legislature has good information if they are going to make decisions about this," Tulleners said.
David Howitt, professor of chemical engineering and materials science and chair of the Graduate Group in Forensic Science at UC Davis, supervised the project. Howitt said that while the technique tested here has limitations, there are other possible ways to implement microstamping. For example, an ultra-hard ceramic that would be extremely difficult to file off could be used to make the impression, instead of the relatively soft firing pin.
More university involvement is needed to address these sorts of forensic science issues from their inception, Howitt said.
UC Davis offers a master's degree in forensic science through UC Davis Extension. Courses are taught by an interdisciplinary group of UC Davis faculty and outside experts. The program currently has an enrollment of about 60 students.
The technology developed by ID Dynamics of Londonderry, N.H., uses a laser to cut a pattern or code into the head of a firing pin. The method is similar to that used to engrave codes on computer chips. When the trigger is pulled, the firing pin hits the cartridge case or primer and stamps the code onto it. In principle, the spent cartridge can then be matched to a specific gun.
If successfully implemented, microstamping would be one additional piece of evidence for investigators to gather in building a criminal case, said Fred Tulleners, director of the forensics program at UC Davis. Tulleners was formerly director of the California Department of Justice crime lab in Sacramento, as well as the Sacramento and Santa Rosa county crime labs.
UC Davis graduate student Michael Beddow tested firing pins from six different brands of semi-automatic handguns, two semi-automatic rifles and a shotgun. The firing pins were engraved with three different types of code: a letter/number code on the face of the firing pin; a pattern of dots or gears around the pin; and a radial bar code down the side of the pin.
To test the effects of repeated firing, Beddow fitted engraved firing pins into six Smith and Wesson .40-caliber handguns that were issued to California Highway Patrol cadets for use in weapons training. After firing about 2,500 rounds, the letter/number codes on the face of the firing pins were still legible with some signs of wear. But the bar codes and dot codes around the edge of the pins were badly worn.
"They were hammered flat," Beddow said.
Tests on other guns, including .22, .380 and .40-caliber handguns, two semi-automatic rifles and a pump-action shotgun, showed a wide range of results depending on the weapon, the ammunition used and the type of code examined, Beddow found. Generally, the letter/number codes on the face of the firing pin and the gear codes transferred well to cartridge cases, but the bar codes on the sides of the firing pin performed more poorly. Microstamping worked particularly poorly for the one rimfire handgun tested.
The researchers did not have access to information allowing them to read the bar- or gear-codes, and so could not determine if these remained legible enough to be useful.
Codes engraved on the face of the firing pin could easily be removed with household tools, Beddow found.
The researchers estimated that setting up a facility to engrave the firing pins of every handgun sold in California would cost about $8 per firing pin in the first year, falling to under $2 per firing pin in subsequent years, Tulleners said.
Tulleners said that a larger test of about 3,000 firing pins, from a wider range of guns, would allow for a more "real-world" test of the technology. About 650 brands of handguns are sold in California, compared with the nine tested, Beddow estimated in the study. A bigger study would also help show how useful this technology might be in detecting and preventing crime.
The study was commissioned by the California Policy Research Center at the request of the California Legislature.
"We want to make sure that the legislature has good information if they are going to make decisions about this," Tulleners said.
David Howitt, professor of chemical engineering and materials science and chair of the Graduate Group in Forensic Science at UC Davis, supervised the project. Howitt said that while the technique tested here has limitations, there are other possible ways to implement microstamping. For example, an ultra-hard ceramic that would be extremely difficult to file off could be used to make the impression, instead of the relatively soft firing pin.
More university involvement is needed to address these sorts of forensic science issues from their inception, Howitt said.
UC Davis offers a master's degree in forensic science through UC Davis Extension. Courses are taught by an interdisciplinary group of UC Davis faculty and outside experts. The program currently has an enrollment of about 60 students.
BrassTRAX helps police in Palm Beach County match guns to killers
West Palm Beach - The .40-caliber Glock handgun stolen from a sheriff's deputy claimed the lives of four men in three days and left a trail of evidence in its bullet cartridges, discarded at the murder scenes.It was a bloody November 2004 in the city.Two double homicides on Palm Beach Lakes Boulevard, labeled revenge killings by police, prompted outcry and community leaders organized rallies. Police told the public the attacks were planned, not random. The only clue detectives had was that the killer used the same gun in the four slayings.Detectives solved the case by connecting all the bullets using the National Integrated Ballistics Identification Network, or NIBIN. The database analyzed the distinct markings on each of the bullets — linking them to one gun and one killer.
The case was so successful that West Palm Beach police recently bought BrassTRAX, a camera system that allows officers to capture images of those markings."The gun has the fingerprint, it has its own unique microscopic detail," said Palm Beach County Sheriff's Office senior forensic scientist Omar Felix. "That fingerprint is impressed into the cartridge case or on the bullet when it's shot out of the barrel."When police retrieve bullet cartridges from a crime scene, they analyze and enter details of the markings into NIBIN, the national database. The database will repeatedly search to see if that gun has been used in other crimes.When officers retrieve a gun, they shoot a bullet into a metal tube called a "bullet catcher." The officer then removes the bullet cartridge and records the markings the gun made in BrassTRAX. That image is then input into the national database.West Palm Beach police started using the BrassTRAX system — paid for with $100,000 from the county's Criminal Justice Commission — in March. The purchase makes West Palm Beach police the second police agency in the county that can enter bullet cartridge images into the national network.The Sheriff's Office has used the NIBIN network since 2001 and all the police agencies in the county used to take their bullet evidence there. West Palm Beach's newer technology will help reduce the Sheriff's Office workload and cut the sometimes months-long wait to make entries, officials said.Riviera, Delray and Boynton Beach police departments are also authorized to input their information into the database using the West Palm Beach Police Department's BrassTRAX.The West Palm Beach Police Department also enters information from officers' guns into the system in case one is stolen and used, like the deputy's gun that was used in the November 2004 double homicides.Detectives said those cases — where four men were slain in a hail of bullets from the handgun and two other firearms — are a good example of how tracing a gun or bullets can lead investigators to a killer."We had no witnesses, we had nothing except expended shell casings and projectiles from the victims," said West Palm Beach police Detective Donald Iman.Investigators began comparing those bullets and were able to link them to one gun — the Glock. The bullet evidence was the key to linking Derek Dixon to the slayings."It's evidence if we can prove that gun was in one person's hands," Iman said.Police arrested Dixon as a suspect in a carjacking case nearly two months after the killings. He was charged with the murders based on the testimony of a co-defendant and a recorded conversation from the county jail where he admitted to the murders, according to police reports. In March, Dixon, 22, pleaded guilty to the four counts of second degree murder and is now serving 40 years in federal prison for the killings, which will run at the same time as the 40 years he's already serving for carjacking and possession of a firearm by a convicted felon.Iman documented how the gun evidence and the national network helped map out Dixon's rampage:To get the sheriff's deputy's gun from the thief who stole it, Dixon traded some stolen jewelry in a street deal in July 2004.Using the ballistics database to match the bullets fired at each of the scenes, police traced Dixon's attacks between August and December 2004.He was later identified from surveillance camera images of a Steak 'n Shake restaurant shooting in August. No one was injured but bullet cartridges were left behind.On Sept. 25, Dixon fired the handgun after a fight at a nightclub on Okeechobee Boulevard but again no one was injured, police said. Victims refused to cooperate but police found more bullet cartridges.The first double homicide occurred on Nov. 4 when Dixon thought the victims, Reynold Barnes, 23, and Eddie Lee Gibbs, 26, were the people he was firing at in the Steak 'n Shake incident. After leaving an IHop Restaurant, Dixon fired the Glock handgun and another shooter fired a .380 Beretta, police said.Gibbs and Barnes were hit at least 10 times and died.Three days later on Nov. 7, Dixon saw Larry Turner, 23, who he thought tried to kill his brother. He followed a car with three people in it and opened fire in a drive-by shooting. Turner was injured but Ali Jean and Turner Norwood, both 22, were killed and bullet cartridges from the handgun were left behind.At a carjacking Dec. 3 outside an Arby's restaurant in Palm Beach Gardens, shots were fired and a Glock handgun was dropped at the scene.It was the one police were looking for
The case was so successful that West Palm Beach police recently bought BrassTRAX, a camera system that allows officers to capture images of those markings."The gun has the fingerprint, it has its own unique microscopic detail," said Palm Beach County Sheriff's Office senior forensic scientist Omar Felix. "That fingerprint is impressed into the cartridge case or on the bullet when it's shot out of the barrel."When police retrieve bullet cartridges from a crime scene, they analyze and enter details of the markings into NIBIN, the national database. The database will repeatedly search to see if that gun has been used in other crimes.When officers retrieve a gun, they shoot a bullet into a metal tube called a "bullet catcher." The officer then removes the bullet cartridge and records the markings the gun made in BrassTRAX. That image is then input into the national database.West Palm Beach police started using the BrassTRAX system — paid for with $100,000 from the county's Criminal Justice Commission — in March. The purchase makes West Palm Beach police the second police agency in the county that can enter bullet cartridge images into the national network.The Sheriff's Office has used the NIBIN network since 2001 and all the police agencies in the county used to take their bullet evidence there. West Palm Beach's newer technology will help reduce the Sheriff's Office workload and cut the sometimes months-long wait to make entries, officials said.Riviera, Delray and Boynton Beach police departments are also authorized to input their information into the database using the West Palm Beach Police Department's BrassTRAX.The West Palm Beach Police Department also enters information from officers' guns into the system in case one is stolen and used, like the deputy's gun that was used in the November 2004 double homicides.Detectives said those cases — where four men were slain in a hail of bullets from the handgun and two other firearms — are a good example of how tracing a gun or bullets can lead investigators to a killer."We had no witnesses, we had nothing except expended shell casings and projectiles from the victims," said West Palm Beach police Detective Donald Iman.Investigators began comparing those bullets and were able to link them to one gun — the Glock. The bullet evidence was the key to linking Derek Dixon to the slayings."It's evidence if we can prove that gun was in one person's hands," Iman said.Police arrested Dixon as a suspect in a carjacking case nearly two months after the killings. He was charged with the murders based on the testimony of a co-defendant and a recorded conversation from the county jail where he admitted to the murders, according to police reports. In March, Dixon, 22, pleaded guilty to the four counts of second degree murder and is now serving 40 years in federal prison for the killings, which will run at the same time as the 40 years he's already serving for carjacking and possession of a firearm by a convicted felon.Iman documented how the gun evidence and the national network helped map out Dixon's rampage:To get the sheriff's deputy's gun from the thief who stole it, Dixon traded some stolen jewelry in a street deal in July 2004.Using the ballistics database to match the bullets fired at each of the scenes, police traced Dixon's attacks between August and December 2004.He was later identified from surveillance camera images of a Steak 'n Shake restaurant shooting in August. No one was injured but bullet cartridges were left behind.On Sept. 25, Dixon fired the handgun after a fight at a nightclub on Okeechobee Boulevard but again no one was injured, police said. Victims refused to cooperate but police found more bullet cartridges.The first double homicide occurred on Nov. 4 when Dixon thought the victims, Reynold Barnes, 23, and Eddie Lee Gibbs, 26, were the people he was firing at in the Steak 'n Shake incident. After leaving an IHop Restaurant, Dixon fired the Glock handgun and another shooter fired a .380 Beretta, police said.Gibbs and Barnes were hit at least 10 times and died.Three days later on Nov. 7, Dixon saw Larry Turner, 23, who he thought tried to kill his brother. He followed a car with three people in it and opened fire in a drive-by shooting. Turner was injured but Ali Jean and Turner Norwood, both 22, were killed and bullet cartridges from the handgun were left behind.At a carjacking Dec. 3 outside an Arby's restaurant in Palm Beach Gardens, shots were fired and a Glock handgun was dropped at the scene.It was the one police were looking for
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