Crime Scene Diagramming

Question 1

What are 3 purposes of crime scene sketches?

Answer 1

1) Showing scene layout
2) Illustrating spatial relationships
3) Clarifying objects/features from notes/photos

Question 2

A sketch will depict possible paths of (HINT: 3 things)…

Answer 2

Entry, exit, and movement through the scene

Question 3

In what 3 situations will you have to create a sketch?

Answer 3

1) Violent crimes
2) Crimes against children
3) Death investigation

Question 4

What 5 items should you include in your rough sketch?

Answer 4

1) Title block
2) Legend
3) Compass
4) The diagram itself
5) Points of reference

Question 5

Should you fix the evidence or the scene first?

Answer 5

Evidence

Question 6

What does it mean to “fix the evidence?”

Answer 6

Establishing an object’s in-situ location/position

Question 7

Why is it important to fix the evidence first, before the scene?

Answer 7

To minimize the likelihood of accidentally moving an item before its documented

Question 8

When fixing your evidence, how many times minimum should you measure where the evidence is?

Answer 8

Twice

Question 9

What does a bird’s eye view sketch detail?

Answer 9

The entirety of the scene from an aerial view

Question 10

What does a cross projection (exploded) sketch detail?

Answer 10

The entirety of the scene, similar to the bird’s eye view, but the walls are drawn flat on the ground

Question 11

What does an elevation sketch detail?

Answer 11

Various points of elevation from a sideways view

Question 12

Elevation sketches are useful in determining…

Answer 12

Bullet trajectory

Question 13

What does a three-dimensional sketch detail?

Answer 13

Quite literally a 3D model of the scene

Question 14

Why is it better to use a measurement log instead of writing your measurements on your rough sketch?

Answer 14

The rough sketch gets too messy eventually

Question 15

What types of scenes is rectangulation most suited for?

Answer 15

Scenes with defined boundaries, such as a room or house

Question 16

How is evidence fixed via rectangulation?

Answer 16

You measure the evidence at right angles from the evidence to the surrounding walls

Question 17

How is evidence fixed via triangulation?

Answer 17

You take 2 line measurements from 2 distinct landmarks to one point on the evidence to form a triangle (be sure to repeat this for 2 fixed evidence points)

Question 18

What are the best 2 environments for a transecting baseline measurement?

Answer 18

1) Outdoor scenes
2) Very large indoor rooms

Question 19

Can you randomly choose a baseline for a scene?

Answer 19

No. The baseline should be set and repeatable

Question 20

What 2 measurements are needed to create a baseline?

Answer 20

1) Length of the baseline itself
2) Length 90 degrees off the baseline

Question 21

When getting the 90 degree measurement from the baseline, you should…

Answer 21

Note the cardinal direction

Question 22

What tool does the polar coordinate measuring style use?

Answer 22

Azimuth circle

Question 23

What type of scene is the azimuth circle best used for?

Answer 23

Outdoor scenes with largely scattered evidence

Question 24

When using the azimuth circle, which direction should the 0-degree mark be positioned?

Answer 24

North

Question 25

What 3 tools does the total station measurement style use?

Answer 25

1) Automatic transits
2) Lasers
3) Computers

Question 26

What is a pro of the total station measuring style?

Answer 26

It is the most accurate and easy to translate into a final sketch

Question 27

What is a con of the total station measuring style?

Answer 27

It’s very expensive

Question 28

Should a finished sketch be drawn to scale?

Answer 28

Yes

Question 29

What do CAD programs do?

Answer 29

Create 3D finished sketches

Question 30

What does CAD stand for?

Answer 30

Computer-Aided Drafting