Unit Three Text Questions

1. What are the four types of evidence in a criminal investigation? The four types of evidence in a criminal investigation are physical, documentary, a testimony and demonstrative evidence.

2. What are individual characteristics? Give an example of an individual characteristic? Individual characteristics are characteristics that can be traced back to a person or item. An example of an individual characteristic are finger prints.

3. What is the difference between individual characteristics and class characteristics? The difference between individual and class characteristics are that class characteristics can only be connected to a group of sources while an individual characteristic can be traced to a single object or person.

4. What are physical and chemical properties? Give an example of each. Physical properties describe an object can be its weight, size, color, volume, etc. Chemical properties describe how one substance reacts with another such as dropping an Alka-Seltzer tablet into water.

5. What do forensic scientists do to collect and preserve soil samples? Soil samples are collected within a 100 yard radius of certain spots. If dirt were to be found on the bottom of a shoe, then they will bring the entire shoe along with the dirt on it into the lab.

Critical Thinking Questions
1. Why do you think forensic scientists are so careful that the tests they do are sensitive, reproducible, and specific? What might happen if they were less careful about this? I think that forensic scientists are very careful in the tests because performing each test correctly will provide the most evidence. If they were less careful about the tests, I believe that the tests would show traits about evidence that are not true and would lead answers incorrectly.

2. Which type of evidence do you think is most useful in an investigation? Why? I believe that the most useful evidence in an investigation would be physical as it can help forensic scientists understand what happened at a crime as well as identify a suspect.

3. Why do you think that forensic scientists continue to look for class characteristics given their limitations? I think that forensic scientists look for class limitations because it helps narrow down and piece a crime together.

4. What do you think would be some of the challenges in collecting and preserving impressions? Why? I think that some of the challenges in collecting and preserving impressions would be collecting imprints on dust as you would have to try very hard to preserve the imprint as you try to lift the print with tape.

5. If you were on a jury, do you think you would expect individual characteristics in the evidence? Why or why not? What effects might it have if individuals expect to have individuals characteristics presented? If I were to be on jury, I wouldn’t expect individual characteristics in the evidence because not every single case really has the evidence for individualized characteristics. If it were to be expected of everyone then it still may not be enough to convince the jury that the convicted is guilty.