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Visually Impaired Transcript: Cartridge Case SRM Video

VISUAL: Fade up from black to closeup of a gun. Gun fires twice.

Narrator: GUNSHOTS ARE FIRED … A CRIME IS COMMITTED …

VISUAL: Video of suspect running away from shooting.

Narrator:THE SUSPECT ESCAPES …

VISUAL: Closeup of yellow "crime scene tape" seen fluttering.

Narrator: THE EVIDENCE LEFT BEHIND COULD HELP BRING THE SHOOTER TO JUSTICE.

VISUAL: Wide shot of forensic lab technician examining a cartridge case.

Narrator: PROBABLY … THAT EVIDENCE WILL INCLUDE ONE OF THE MORE THAN 200-THOUSAND SHELL CARTRIDGE CASES RETRIEVED EACH YEAR AT CRIME SCENES IN THE U.S.

VISUAL: Closeup of technician placing cartridge case on a microscope.

Narrator: TO THE TRAINED STAFF OF A FORENSICS LAB … A RECOVERED CASE IS LIKE A BALLISTIC FINGERPRINT.

VISUAL: Medium shot of technician looking at microscope image of cartridge case head on monitor. He points to the markings on the case left by the firing of a gun.

Narrator: THAT'S BECAUSE FIRING A GUN LEAVES A UNIQUE PATTERN OF MARKS IMPACTED ON THE SURFACE OF THE SHELL.

VISUAL: Cut to digitized image of blue-colored, doughnut-shaped mark seen on microscope image of cartridge case head. Image rotates slightly.

Narrator: KNOWN AS A "CASE SIGNATURE" …

VISUAL: Cut to monitor screen showing rapidly changing digitized images of case marks as they are pulled from a computer database.

Narrator: THIS PATTERN CAN BE COMPARED TO THOUSANDS STORED IN A NATIONAL DATABASE.

VISUAL: Wide shot of two technicians looking into microscopes.

Narrator: IF THERE'S A MATCH … A FORENSICS LAB CAN IDENTIFY THE SPECIFIC FIREARM USED IN A CRIME.

VISUAL: Images of two cartridge case head with markings are seen on monitor using split-screen. The images are slowly brought together to see if they are a match.

Narrator: THAT IS … IF THEY CAN PROVE THE MATCH IS ACCURATE SO THAT THE FINDING HOLDS UP IN COURT.

VISUAL: Dissolve to video of entrance sign at NIST headquarters in Maryland.

Narrator: THANKS TO THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY … THAT TASK JUST GOT A LITTLE EASIER.

VISUAL: Cut to NIST program manager Robert Thompson seated in forensic lab with microscope in background.

Robert Thompson: "Crime laboratories are increasingly under pressure to show that they follow good standard practice, to show accuracy in their examinations. In the firearms identification laboratories, NIST has given them the opportunity to use a standard bullet about seven years ago, and now, we've just rolled out a standard cartridge case for them to use."

VISUAL: Zoom out from closeup of standard cartridge case on microscope stage to shot of technician adjusting the scope's controls.

Narrator: THE NEW NIST STANDARD STARTED ITS LIFE WHEN THE AGENCY ACQUIRED A CARTRIDGE CASE FROM THE BUREAU OF ALCOHOL, TOBACCO AND FIREARMS THAT HAD DISTINCTIVE EXAMPLES OF THE THREE MOST IMPORTANT CASE SIGNATURES:

VISUAL: Cut to full-screen image of cartridge case head. As the name of each of the three markings is mentioned, it is located on the case head with an abbreviation (FP for firing-pin impression, BF for breech-face impression, and EM for ejector mark).

Narrator: THE FIRING-PIN IMPRESSION … THE BREECH FACE IMPRESSION …

AND THE EJECTOR MARK.

VISUAL: Closeup of cartridge case on microscope stage.

Narrator: TO MAKE IDENTICAL COPIES OF THIS CASE AND ITS MARKINGS …

VISUAL: Wide shot of two technicians adjusting the controls of their microscopes.

Narrator: NIST'S FORENSIC SCIENTISTS TURNED TO A TECHNIQUE KNOWN AS ELECTROFORMING.

VISUAL: Graphic showing metal block in solution with "plus sign" above it to indicate that the block is positively charged. Small dots are seen streaming out from the block. Above the graphic are the words "Microscopic metal particles."

Narrator: SIMILAR TO THE METHOD BY WHICH JEWELERS COVER OBJECTS WITH SILVER OR GOLD...

VISUAL: A cartridge case appears in the graphic with a "minus sign" above it to indicate it is negatively charged. Above the graphic are the words "Template Case."

Narrator: ELECTROFORMING WAS USED TO SURROUND THE TEMPLATE CASE

VISUAL: More small dots are seen streaming from the metal block to the case which now has a thick coating around it. Above the graphic are the words "Metal coats template case."

Narrator: WITH A THICK METAL COATING.

VISUAL: Graphic changes to show replica cartridge case. Above the graphic are the words "Solidified coating becomes mold."

Narrator: ONCE THE COATING SOLIDIFIED AND THE SHELL INSIDE WAS REMOVED … A NEARLY PERFECT NEGATIVE MOLD WAS LEFT BEHIND.

VISUAL: Cut to NIST engineer Alan Zheng on camera.

Alan Zheng: "When I first received the replica cases, I compared them to the master casings that they were produced from. And to my eyes, I could not tell any difference between the two. That's because the mold is so accurate that it is able to pick up feature sizes 100 times smaller than the width of a human hair."

VISUAL: Medium shot of cartridge case on microscope stage.

Narrator: ALONG WITH PRODUCING THE REPLICA CARTRIDGE CASE …

VISUAL: Cut to "golden image" of cartridge case marks seen on monitor as it is compared to those on another cartridge case.

Narrator: NIST AND THE ATF ALSO CAPTURED ITS SIGNATURE MARKS IN DIGITAL IMAGES

VISUAL: Closeup of microscope lenses being turned by technician.

Narrator: TAKEN WITH THE SAME TYPE OF MICROSCOPE USED TO ENTER CASE SIGNATURES INTO THE NATIONAL DATABASE.

VISUAL: Medium shot of technician looking into microscope.

Narrator: FOR ACCURACY … A FORENSIC LAB

VISUAL: Cut to monitor screen showing "golden image" being compared to another cartridge case.

Narrator: CAN COMPARE THESE "GOLDEN IMAGES" TO ONES THEY ACQUIRE OF THE NIST REPLICA CASE.

VISUAL: Closeup of standard cartridge case on microscope stage.

Narrator: IF THEY MATCH … THE STAFF CAN REST ASSURED THAT THEIR RESULTS

VISUAL: Wide shot of technicians at microscopes.

Narrator: WILL BE IN SYNC WITH ALL OTHER FORENSIC LABS THAT USE THE STANDARD.

VISUAL: Cut to wide shot of technician as he holds standard cartridge case in front of the camera.

Narrator: TOGETHER … THE REPLICA SHELL CASES AND THE GOLDEN IMAGES COMBINE TO MAKE A POWERFUL CRIMEFIGHTING TOOL …

VISUAL: Cut to technician as he holds up the Standard Reference Material certificate in front of the camera.

Narrator: NIST STANDARD REFERENCE MATERIAL 2461.

VISUAL: Cut to NIST engineer Brian Renegar on camera.

Brian Renegar: "For instance, let's say there was a crime committed in California and there maybe was another crime committed in New York City, and the examiners wanted to compare the evidence to see if there was a match between the two crimes. One way they can do this is by using a national database to correlate the images together. However, they need something to make sure there's quality control that the images were acquired correctly and that's where the NIST standard casing comes in."

VISUAL: Cut to video showing crime suspect being handcuffed.

Narrator: AFTER ALL … NIST AND ITS PARTNERS IN LAW ENFORECMENT WANT TO MAKE CERTAIN THAT CRIMINALS WHO USE GUNS DON'T GET AWAY WITH THEIR CRIMES.

VISUAL: Dissolve to credits (five pages). Text on screens read as follows:

Still images, animations and video used with permission by:

NIST Law Enforcement Standards Office
NIST Physical Measurement Laboratory
Revostock
Shutterstock

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NIST Video Production Staff

Narrator: Chad Boutin
Producer/Scriptwriter: Michael E. Newman
Videographer: Leon Gerskovic
Videographer/Editor: Sabrina Xaviar

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For more information on the NIST ballistic SRMs, including ordering instructions: www.nist.gov/srm/index.cfm

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The display of products and services in this program is for demonstration purposes only and does not imply an endorsement by NIST.

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Produced by
National Institute of Standards and Technology Public Affairs Office

August 2012

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VISUAL: Fade to black.