Section 5.5 Flashcards
Example, muddy patch with a footprint we can determine by how deep the footprint goes how much what?
The suspect may have weighed
Walking footprints are different from running footprints because they leave different depths. This determines what?
Speed
This can be individualized down to the individual. Example, there is an impression of exactly this shoe and this size at the crime. They cannot tell just by that because there are multiple same shoes. However, the _____ ______ may be different.
wear pattern
Because the wear pattern is different their is something distinct and if it is present on the footprint and the shoe it can potentially prove it was you. True or False
True
If you are walking around and unsure of where you are going this can show what in the footprints?
hesitance
Example, tracks in a business and there is __________ you can eliminate any of the other employees because they would not b e what?
HESITANCE
weight speed wear patterns hesitance unaware of terrain direction of travel
Shoe and tire prints
Arrive at a fresh scene and there are tire tracks tearing out of the place and heading south on this road. You can tell the other officers that you know which way the suspect is going so they can follow it based on what?
Direction of travel
When you get a shoe or tire print you want to do what?
Make a cast
Get a marker or ruler and lay it next to the print and get photos. After it has been documented well make a ______.
Cast
What is made with a white powder and add water and mix it and pour it onto a track and leave it until it Harden and now you have a perfect negative of a print?
cast
Does it always work when you make a cast or could you mess it up?
You could mess it up that is why it is important to take photos and document
Are bite marks on skin accurate?
no
Bite-marks in chewing gum that the suspect left at the sense could be matched because it leaves a detailed impression. True or False
True
Forensic odontologists in the last 10-20 years have said that what is not accurate?
bite marks
There are people in prison for something they did not do because they were matched to a bite mark that was not theirs. True or False
True
Does every tool leave a mark?
Yes
Example, pry bar breaking and entering.
leaves a tool mark
It is easy to tell what tool made the mark but it is more difficult to tell the specific tool. True or False
True
Firearm crime: First thing the officer looks at is the what?
rifling
Grooves on the metal inside of the gun that the bullet spirals on when it comes out of the gun is what?
rifling
By the time the bullet leaves the gun it is spinning. Why?
to make it go straight
The grooves in the rifling catch the bullet and make it do what?
Spin
Prior to the revolutionary war we just fired spheres and muskets and they were not accurate because they did not have what?
rifling
Different brands of guns have different rifling. True or False
True
If you look at the spent bullet and it survived the impact, we can look at the rifling to determine who the gun belongs to. True or False
True
Every time you shoot the gun various changes happen to the inside of the gun and make it a more distinct pattern to show the specific gun it comes from. True or False
True
If the bullet casing have the exact same ______ on the projectile you can tell the bullet from the crime scene came from that gun.
Striations
What makes the initial spark in the gun?
Primer
When a gun goes off and you pull the trigger and the firing pin flies forward and punctures the primer and that provides a spark and the gun powder and the gun goes Ka-boom. True or False
True
All the pressure created can only go out and as it goes it pushes the bullet down the gun and out. True or False
True
What becomes distinct over time?
firing pin
If you can get an ejected shell casing, you can look at the mark that the firing pin made in the primer and you can use that to do what?
Find the specific gun
When the gun has been fired there is a mechanical piece in the gun called the ________ that comes in and grabs the bullet and tosses it out and puts a new bullet in.
Extractor
Does the extractor leave a mark?
Yes
Rifling Striations Firing Pin Impressions Extraction Marks Gunshot residue
Firearms
Does gun powder burn perfectly?
No
Out of the barrel of the gun there is a poof of unburned powder. It is fairly microscopic and it gets onto the hands of the person firing the gun. True or False
True
Glass is laying all over at a crime scene and if there is a lot of it lying around we can look at the suspect to see if their shoes have that glass in them. True or False
True
In shooting cases where a bullet goes through the window can you tell which bullet went through first?
Yes based on the cracks
When a crack hits an already existing crack what happens?
It stops
Soil can be taken or left at the crime scene. True or False
True
Example, crime scene and there is a footprint in the dirt from the bad guy and we find that the soil is not from around here. We can use it to determine where the suspect is from. True or False
True
example, we find a dead body way in the middle of nowhere and we take soil samples and get the suspects boots and we match it to the area found, True or False
True
Two things need to be determined when looking at two things
1.
2.
- what kind of dirt it is
2. what kind of pollen do you find in the dirt
Most of this falls into the ground and goes into the dirt.
Pollen
Based on the kinds and the amount of pollen on the dirt we can be more specific. True or False
True
If you find specific soil where the body was found, we can tell that the person was at least in the are and it is good circumstantial evidence that he is the one the dumped the body. True or False
True
