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ALIAS: The Next Generation of Forensic Ballistics
Written by Michael Barrett
The faster a ballistics lab can get cartridge identification data to police investigators, the quicker they can solve gun crimes and make arrests. Law enforcement organizations that rely on legacy ballistics systems face significant bottlenecks. Existing forensic tools have not evolved with advances in available technologies. At the same time, forensics examiners face an escalating need to accurately match cartridges with firearms.
ALIAS (Advanced balLIstics Analysis System) alleviates those bottlenecks and provides firearms examiners with a next generation ballistics analysis system that solves more crimes and saves more lives.
Forensic ballistics gained prominence following the Saint Valentine’s Day Massacre on Feb. 14, 1929. Investigator Calvin Goddard examined the slugs and expended cartridge cases recovered from the bloody crime scene using the first generation of the comparison microscope. He first proved the police were not involved (two killers impersonated police officers), and then later he identified machine guns used by the hit men.
The metals used to make firearms are harder than the metal components of ammunition. When a firing pin strikes a cartridge or when a firearm ejects an expended cartridge, these actions leave distinct impressions called tool marks on the cartridge. The tool marks produced when someone fires a weapon are unique and reproducible—this fact is the foundation of forensic ballistics. The methods used to identify, catalog and correlate tool marks have come a long way since Goddard’s time.
In 1991, electronic and digital science was used to compare fired bullets and cartridge cases. These techniques came together under the Integrated Ballistics Identification System (IBIS). Though it is currently the most widely used forensic ballistics system in the world — and responsible for solving thousands of firearms crimes — IBIS has fallen behind the technology curve. What was needed was a simpler-to-use, more accurate, scalable and less expensive system that takes advantage of the huge advances in 3-D imaging that have occurred since the early 1990s.
Pyramidal Technologies assembled a technology and ballistics imaging team to develop and introduce the next generation in forensic ballistics to law enforcement agencies around the world. In October 2009, ALIAS was introduced at the European Network of Forensic Science Institutes Working Group Meeting Firearms/GSR in Wiesbaden, Germany.
Compared to existing ballistics analysis tools that require as many as seven steps to operate, the three-step ALIAS protocol delivers easy-to-use operation, quicker ramp-up times and a smaller margin of error. Once users sign into ALIAS, they can search the database for existing cartridge data or create a new case file using a simple form. For test-fire cartridges, the form includes additional fields for information on the firearm used in the test.
Next, examiners launch a cartridge scan. Unlike existing systems, ALIAS does not rely on two-dimensional photographs of cartridge casings. ALIAS’s Swiss-built interferometer creates a three-dimensional, topographical image of the surface of the cartridge to a level of accuracy down to two microns (1/50th of a human hair’s width). The ALIAS “point-and-shoot” technology gathers data independently of the orientation of the ballistics specimen.
A single cartridge scan generates 54 Giga points of data representing the total number of grid points measured by the interferometer for a cartridge scan area of 6x6 mm. A typical ALIAS scan produces and stores more than 30 million pieces of data about the surface of the cartridge. No photographic image comes remotely close for accuracy, detail and analytical potential.
ALIAS prompts users for which cartridge to scan—the interferometer can hold up to six cartridges. The user’s selection binds that cartridge’s image to the case file in the database. An unlimited number of cartridges can be associated with a single case.
Once the initial scan completes, ALIAS displays a rendered image of the scan data and asks the user if the scan is acceptable. If so, ALIAS performs further analysis of the image and stores the resulting metadata in its database. Forensic examiners can then search the database for matching cartridges.
Existing systems, including IBIS, attempt to compare visual characteristics of black-and-white photographs of cartridges. In contrast, ALIAS compares millions of measurements of the dimensions of specific cartridge features and their positions on the cartridge. It then sorts the cartridges on that data and presents the operator with only those cartridges most closely matching the subject cartridge.
The correlation interface shows the subject cartridge case and a group of the best matches found in the database. The examiner can then compare the subject cartridge case and any matching cartridge case in a powerful visualization interface. ALIAS renders images in natural color, grey-scale or topographically sensitive color, and lets users easily switch between these views.
Each rendered cartridge image includes its own tool dock that offers a rich set of options to enhance and view the 3-D image. The rendered cartridge images are light-independent. Just by clicking and dragging the virtual light source tool, examiners can rotate the light direction and angle to increase shadows and further highlight minute marks and surface features—something that is impossible with a photograph.
By increasing the Z-Scale (with a click and drag of the slider), examiners can zoom in and enhance the breech face markings. A forensic examiner can split two cartridge images vertically and slide them together to determine if the halves match. This mimics the use of the comparison microscope— the principle tool used for more than half a century. In a typical cartridge case examination, a forensic examiner would switch between the correlation interface and the visualization interface as often as needed to find the correct match.
Users can view and compare multiple images either side by side, superimposed, through color changes on the matching area, with zoom comparison, or by visualizing non-matching areas. With more than 30 million pieces of data stored for each cartridge case, the analytical possibilities are nearly endless, and as new tools become available, they can utilize the same data. With the ability to visually examine cartridge tool marks as little as two microns in size, comparison accuracy is unprecedented.
ALIAS was designed on an open architecture to make data sharing possible. Any law enforcement agency that wishes to use ALIAS ballistics data in another computer program can access the data through the ALIAS Application Program Interface (API). Sharing data promotes faster convictions in gun crimes.
Users can export ALIAS cartridge case scan data and case-related demographic data in a variety of formats to departmental, national or international forensic databases, or to private firms for further analysis of the available data. For example, you can export a CSV file for use in plotting programs and high-end analysis tools. The data is accessible for everyday use as well. If someone needs a JPG image for a presentation or a PDF report of a cartridge and its case data, ALIAS can provide it.
ALIAS leverages the Mac Pro platform—currently the fastest computer that Apple offers—and the most recent Mac operating system, called Snow Leopard. This lets users take advantage of Apple’s advanced features, including 64-bit processing power, superior graphics capabilities, a rich development environment and highly stable Unix operating system. Although ALIAS was designed to stand alone as a turnkey system, it easily integrates into existing IT infrastructures.
Solve more crimes. Convict more criminals. Save more lives. With ALIAS firearms, examiners and operators can analyze cartridge data faster and with greater accuracy than with existing systems. The net result is that crime investigators can identify and apprehend violent criminals more quickly and expect a higher level of convictions.
Mike Barrett is the president and CEO of Pyramidal Technologies. He is a former Forensic Firearms Examiner for the Royal Canadian Mounted Police and former Technical Lead-Firearms for the San Mateo County, CA Sheriff’s Office. He may be reached at email@example.com.
Published in Law and Order, Mar 2010
Rating : 7.3
Related CompaniesPyramidal Technologies
Related ProductsForensic Ballistics
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