Hello Forensics students, The third two weeks of doing school … · 2020-04-30 · 8 Forensic...

Hello Forensics students, Once again, I miss you and hope you are well! The third two weeks of doing school from home will occur from May 4th to May 15th. We will be moving on to Chapter 17: Ballistics. This is formatted a little differently than in the past. There is a power point and two readings attached. There is then a test that can be completed using the power point and readings. This will be the last assignment for seniors. Juniors will have one more small assignment to close out the year. You do NOT need to print anything out. Please put your name and answers to the test in a document or on a piece of paper. There are several options for turning in your work:

1. Use a google doc and share with me 2. Type answers into an email and send to me 3. Take pictures of your hand-written work and email to me

o My email is [email protected] 4. If you are unable to submit things electronically that is okay! Instead, bring to

the school and drop off in the drop off bin at the teacher entrance at the high school or use the work/lunch swap.

Please feel free to email me with any questions or concerns that you may have. In the meantime, stay safe! Miss Fisher

May the fourth be with you!

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Chapter 17 Ballistics Introduction

Ballistic evidence helps explain: l What type of firearm was used. l The caliber of the bullet.

– Internal diameter of a gun barrell The number of bullets fired. l Where the shooter was. l Whether a weapon was fired recently. l If a firearm was used in previous crimes.

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Forensic Science: Fundamentals & Investigations, Chapter 17 2

History of Gunpowder and Firearms

l The Chinese invented gunpowder over a thousand years ago.

l In the beginning, wicks were used ignite the gunpowder.

l The cartridge loading followed. l Rifling provided greater accuracy. l Revolver, semi-automatic, and automatic

handguns were developed.

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Firearms and Rifling

l Grooves and ridges (lands) in the barrel of a gun produce the twisting that adds accuracy.

l This leaves an individualized pattern on the bullet.

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Bullets, Cartridges, and Calibers

Bullets and cartridges are packaged together. The bullet, usually of metal, is out front with the cartridge, holding the primer and propellant powders, behind.

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How a Firearm Works

1. The firing pin hits the base of the cartridge, igniting the primer powder.

2. The primer powder sparks through the flash hole to the main propellant supply.

3. The pressure of the explosion pushes the bullet from the casing into the barrel.

4. The bullet follows the lands and grooves spiraling out of the barrel.

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Caliber of the Cartridge

l Caliber is a measure the diameter of the cartridge.

l These usually are hundredths of an inch.– Very, very specific!

l Common calibers include .22, .25, .357, .38, .44, and .45.

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The Study of Bullets and Cartridge Casings

1. How is each fired bullet marked? As a gun is fired, the barrel marks each bullet with its own unique pattern of lands and grooves.

2. What is the procedure to match a spent bullet to the firearm that shot it? Investigators compare bullets and spent cartridges shot from the suspected firearm. To get a known bullet for comparison, they test-fire the weapon.

3. What makes up a test-firing, and why is it done? Investigators test-fire the weapon into a water tank or gel block. This captures the bullet without damaging it. Then, they can compare the markings on known bullets with those on the suspect bullets.

Matching grooves (indentations)

Matching lands (elevations)

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Gunshot Residues

l Particles of unburned powder and traces of smoke are the residues of gunshots.

l They can leave a trace on the hand, arm, face, hair, or clothing of the shooter.

l They can also leave a trace on the victim. l Chemical testing often can detect residue even if

removal is attempted. l The distance from the victim to the shooter can be

determined by examination of the residue pattern on the victim.

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Trajectory

l Two reference points are needed to define the trajectory.

l Investigators can figure the shooter discharged the firearm somewhere along that line.

Path of bullet

Horizon

Wind shield

Distance along path of bullet to window, 23.9”

Distance along horizon to window, 23.5”

yx

60 feet

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Trajectory

l Reference points can be bullet holes in objects or victims.

l An entry point and exit point on a victim can be used.

l Gunshot residue or spent cartridge casings can be less specific reference points.

l Investigators can use lasers to trace a straight-line path to help determine the position of the shooter.

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Bullet Wounds 1. Why do entrance wounds tend to be smaller than exit wounds? –The

size of the entry should be smaller than the bullet because skin in somewhat elastic. Exit wounds are generally larger because as the bullet moves through the body, it may collect and carry body tissue and bone with it.

2. If the bullet penetrates clothing, what can fibers embedded in the wound indicate? Fibers imbedded in wounds can indicate the direction of entrance.

3. Where is gunshot residue usually found? Gunshot residue can be found onlyaround entrance wounds

4. If the gun is fired with the muzzle touching the victim’s skin, what telltale mark may show up? The hot gases released from the muzzle flash may burn the skin.

5. Will larger or will smaller caliber bullets tend to lodge within the body rather than passing through? Why? High-speed bullets are more likely to pass through a body. Therefore, small-caliber bullets, such as a .22 caliber, tend to lodge within the body, while larger-caliber bullets will pass through.

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Final

l The final exam will be:– 20 multiple choice coming from this power point.

(40 points)– A reading with 20 questions (40 points)– 80 points in total


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Stopping gun crime - Houston Chronicle

Revamped ballistics network a powerful weapon vs. serial shooters

By St. John Barned-Smith

Emmett Jolley pulled up to the intersection near his northeast Houston home one spring night 14 months ago when the gunfire began.

A hail of bullets riddled his gray Nissan, striking him and a passenger sitting next to him.

The gunman fled moments later, leaving police to pick through the crime scene and bag the shell casings he'd left behind.

Miraculously, Jolley and his friend survived, victims of one of the thousands of gun crimes that plague Houston every year, and one that easily might have gone unsolved in years past.

This time, however, investigators had a weapon of their own - the National Integrated Ballistics Information Network, a revamped ballistics testing program run by the Bureau of Alcohol, Tobacco, Firearms and Explosives.

The bureau has pumped millions of dollars into the program to help local law enforcement make faster and better use of the federal database, creating joint investigative task forces with police in cities most prone to gun violence.

It gives police the clues they need in just days, not months.

"We're looking for a particular gun," said Art Peralta, assistant special agent in charge at ATF's Houston Field Division. "When we find that gun, we're usually going to find the person responsible for pulling that trigger."

Using NIBIN, investigators gained a valuable clue in Jolley's shooting: a ballistics match with a bullet casing from an attempted robbery just three days earlier.

The evidence helped pin the case on 17-year-old Timothy "Dough-Boy Ru" Grimes, an acquaintance who apparently thought Jolley had insulted his girlfriend.

Grimes' guilty plea earlier this month marked the first conviction in Houston using the retooled NIBIN database, part of a new effort by ATF to help local police get trigger-happy criminals off the street.

In the 18 months since the ATF launched the retooled program, NIBIN has generated dozens of leads that led to 20 arrests. Investigators linked one weapon in another case to six different shootings and connected another gun to a known drug dealer they say killed a horse.

"We're going to solve crime sooner, bring criminals to justice sooner, and more often," said Police Chief Art Acevedo. "When we do those things, we're going to ultimately prevent future crimes and save lives."

'Our flashlight'

Gun violence leaves a deadly toll in its wake across Houston annually.

More than 400 people died in the Bayou City from guns in 2016, including 259 homicides and 160 suicides. Gunmen committed 5,457 aggravated assaults with a firearm.

And Houston law enforcement leads the state - by far - in the recovery of firearms. Police seized more than 5,400 guns in Houston in 2015, twice as many as in Dallas and San Antonio, according to the most recent federal data.

In years past, slow ballistics testing left dangerous criminals on the streets for weeks or months while investigators waited for evidence.

Since the same firearms often are used repeatedly - even by different people - tracking the gun can identify an active shooter before another crime is committed. In Memphis, for example, NIBIN linked 30 percent of cases to guns that had been used more than once.

"Those are shooters, the worst of the worst," Peralta said. "NIBIN is our flashlight - it's not going to be able to see the whole room, but it will give us the ability to focus in on specific things."

The database allows firearms experts to match high-resolution photos of marks left on bullet casings after being fired. The guns' firing pins leave a mark unique to each gun, allowing investigators to connect casings fired at different shootings.

Turning NIBIN into the crime-fighting tool agents envisioned, however, didn't go as ATF leaders initially hoped.

Twenty years ago, ATF equipped hundreds of law enforcement agencies and crime labs with ballistic imaging machines and began compiling photos of casings collected at crime scenes or test-fired from guns seized in investigations.

Whipsawing budgets, disinterest and poor implementation at the local level, however, hampered NIBIN's impact on helping stop gun crime.

The problems left some gun cases unsolved, giving repeat shooters more time to wreak havoc. Bodies piled up.

"The right answer, late, doesn't help the investigators any more than the wrong information on time - they need that information quickly," said Ramit Plushnick-Masti, with the Houston Forensic Science Center, an independent lab that tests casings for the Houston Police Department.

ultra-forensictechnology.com

New Ballistics Technology Helps Fire Up 20Year Old Cold Case

Pete Gagliardi

3-4 minutes

This is a story about tenacity and crime solving.

It is a true story about a woman living in a neighborhood who just wanted somepeace and quiet.

Unfortunately, as all true stories do – if followed to their natural conclusions – itends in death. The death of Valentina Giles Rogue almost 20 years ago.

In 1994, according to news reports, Ms. Rogue confronted a group of drugdealers loitering on the street outside her apartment in Santa Ana. Because shespoke up, she was shot in the chest at close range. She still managed to climbback upstairs to her apartment where she collapsed and died in front of her 24-year-old son and his wife.

Although the instrument of the crime, a .25 caliber pistol, was recovered fromone of the prime suspects, Manuel Rojas, the day after the slaying, firearmexaminers in Orange County were unable to link it to the ballistics evidence fromthe murder with the analytical tools that they had at their disposal at that time.

New Ballistics Technology Helps Fire Up 20 Year Old Cold Case about:reader?url=http://www.ultra-forensictechnology.com/n...

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In 2009, cold case detectives investigating the Rogue homicide asked SantaAna Firearms Examiner Rocky Edwards for help.

They were aware that Edwards had travelled to Forensic Technology in Montrealand had successfully used the company's newly developed ballistics analysissystem called IBIS BULLETTRAX-3D to solve another difficult cold case oncebefore.

This time, Edwards contacted the Boston Police Department, the first and onlyone in the U.S. that currently uses the IBIS BULLETTRAX-3D system. TheBoston cops welcomed Edwards allowing him access to their IBISBULLETTRAX-3D system which he used to do what could not be done before -link the Rojas gun to the murder of Valentina Rogue.

Newspapers reported that Rojas was a juvenile at the time Roque wasmurdered and that the Juvenile court lost sentencing jurisdiction over him.However,justice demanded that the case be tried there anyway.

Deputy District Attorney Seton Hunt said that he proceeded with the casebecause: “The family of the victim and the state of California deservefinality and justice - nobody gets away with murder in Orange County.”

At the trial this week, Rojas was convicted of murder in the first degree.Furthermore, the court mentioned that the credibility of Edwards’ workcontributed significantly to the outcome.

Rojas didn't get away "scott-free", even with the juvenile court "catch-22",because he is currently serving life in prison for a string of Orange Countyrobberies in 1998 and 2004.

Congratulations to the Orange County District Attorney, the Santa Ana PoliceDepartment and its Firearms Examiner Rocky Edwards; and to the Boston PDon the conviction yesterday of Manuel Rojas. Their work and dilligence hashelped find justice for Valentina Giles Rogue and bring closure to her survivors.

Every victim everywhere deserves justice and nobody, anywhere should getaway with murder.

In this case it took three things in balance: Outstanding People, EffectiveProcesses and Innovative Technology.

Pete Gagliardi

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New Ballistics Technology Helps Fire Up 20 Year Old Cold Case about:reader?url=http://www.ultra-forensictechnology.com/n...

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Name ________________________________________ Date ______________________ Period _________ Forensics Chapter 17: Ballistics *Each MC worth 2 points, Each OE 2 points à 80 Points total! Multiple Choice

1. Ballistic evidence helps explain _________.

a. What type of firearm was used b. The number of bullets fired c. If a firearm was used in previous crimes d. All of the above

2. Which best defines the caliber of a bullet?

a. Internal radius of a gun barrel b. Internal diameter of a gun barrel c. External radius of a gun barrel d. External diameter of a gun barrel

3. The ______________ are credited with inventing gunpowder.

a. Japanese b. Chinese c. Koreans d. Canadians

4. When was gunpowder first used?

a. Over 100 years ago b. Over 500 years ago c. Over 1000 years ago d. Over 2000 years ago

5. The individualized pattern left on a bullet after firing is due to ______.

a. Grooves b. Lands c. Primer d. Both A and B

6. Which best describes test firing?

a. A process of firing a gun into water or a gel block so that it is not damaged, but captures the individualized markings that appear on the bullet.

b. A process of firing a gun into a block of wood so that it is only minimally damaged, but captures the individualized markings that appear on the bullet.

c. A process of firing a gun through glass so that the amount of damage it can cause is assessed. d. A process of firing a gun into a metal plate so that the amount of damage it can cause is assessed.

7. When a small caliber gun is fired the bullet travels with __________ speed.

a. High b. Moderate c. Low

8. A bullet is most likely passed through a body as opposed to becoming lodged within it when traveling at a ________

speed. a. High b. Moderate c. Low

9. Where may gunshot residue be found on the victim?

a. Around the entrance wound b. Around the exit wound c. Around a bullet that is lodged within the body d. In the blood of the victim

Use the image below to answer questions 10 – 14.

10. 1 is the ____________. a. Case b. Propellant c. Rim d. Bullet e. Primer

11. 2 is the ____________.

a. Case b. Propellant c. Rim d. Bullet e. Primer

12. 3 is the ____________.


13. 4 is the ____________.


14. 5 is the ____________.


15. Which best describes the trajectory of a bullet?

a. The speed by which the bullet leaves the gun. b. The distance the bullet travels in total. c. The age of the bullet. d. The path the bullet follows from the time it leaves the gun until the time it stops.

16. A burn may show up on a victim when _________.

a. The gun is fired within 2 inches of the victim’s body. b. The gun is fired within 5 inches of the victim’s body. c. The muzzle of the gun touches a person’s skin. d. The gun is small in caliber.

17. Which of the following are considered to be gunshot residues? a. Unburned powder b. Burned powder c. Smoke d. Both A and C

18. ________ reference points are needed to determine the trajectory of a bullet.

a. One b. Two c. Three d. Four

19. Bullets are usually made of _______.

a. Wood b. Plastic c. Metal d. Cork

20. A bullet ________ out of a gun barrel.

a. Beelines b. Spirals c. Summersaults

Open Ended Read the attached articles and answer the following questions in Complete Sentences on a separate sheet of composition paper. Article 1: New Ballistics Technology Helps Fire Up 20-Year-Old Cold Case 1. What happened to Valentina Giles Rogue? 2. What weapon was recovered from one of the suspects? 3. Was the weapon able to link the suspect to the crime? Why or why not? 4. The crime happened in 1994, when was it reopened for further investigation? 5. What new technology helped in the solving of this case? 6. Describe Rojas conviction in this case. 7. Why did Rojas not get away “scott-free?”

Article 2: Stopping gun crime- Houston Chronicle 1. What happened to Emmett Jolley? 2. What is the National Integrated Ballistics Information Network? 3. How has the National Integrated Ballistics Information Network helped police solve crimes faster? 4. How did the National Integrated Ballistics Information Network help in solving the Emmett Jolley case? 5. What was Timothy Grimes’ motive? 6. How exactly does the National Integrated Ballistics Information Network link guns to a crime? 7. What makes cartridge casings specific to each firearm? 8. Describe how the imaging machine works. 9. In 2015 and 2016 how big of an issue was gun related deaths in Bayou City and Houston? 10. How has ballistic testing served to curb gun related issues. 11. The same firearm is often used repeatedly. How is this beneficial for police when tracking and catching a shooter? 12. Why has turning NIBIN into a crime-fighting tool not going as well as the ATF leaders initially hoped?

Yearly reflection question: 1. What was your favorite topic or activity we completed during the forensics portion of this class? Why?

Hello Forensics students, The third two weeks of doing school … · 2020-04-30 · 8 Forensic...

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