Field tests can be used at a crime scene rather than sending all
suspected evidence to the lab. If the tests show positive results,
they are then sent to the lab.


Primary Task Response: Within the Discussion Board area, write 400–600
words that respond to the following questions with your thoughts,
ideas, and comments. This will be the foundation for future
discussions by your classmates. Be substantive and clear, and use
examples to reinforce your ideas:


•What types of presumptive tests can be used at a crime scene? Explain.


◦Which of these tests do you think are most prone to error? Why?


◦Which of these tests do you feel is the most important to crime scene
investigators? Why?


•Why do you think an investigator would field test something when it
can be collected and sent to the lab immediately? Explain.


•Can an investigator field test all evidence? Why or why not? Explain.