Reference no: EM131557000

Forensic Chemistry and Trace Evidence Analysis

Discussion

Answer each question with 250 word minimum

1. Driving Under the Influence-Alcohol is a widely used drug in the U.S. and accounts for a multitude of motor vehicle fatalities. Despite the fact that all states have reasonable standards for identifying the drunk driver, until recently, many states defined driving under the influence with different blood-alcohol standards. Discuss the pros and cons of the current uniform national standard to define driving under the influence. Should the Federal government mandate a lower uniform national blood alcohol level standard rather than the current 0.08% standard?

2. Drug Recognition Expert (DRE) Program-What are the advantages and disadvantages of the Drug Recognition Expert (DRE) program in the U.S.?

Seminar

To receive credit for the seminar if you are unable to attend, you are required to write a 300 - 500 word paper on the seminar topic below.
Legalization of Drugs

This week we will discuss whether or not legalization would have any impact on the investigator who must process a crime scene. As you consider this issue, weigh the potential pros and cons of legalization from the perspective of the modern crime lab.

You will also discuss different classes of drugs and review some of the analytical techniques used by forensic drug chemists and toxicologists to identify suspected illegal drugs.

Assignment

Forensic Drug Chemistry and White Powder Identification Experiment

The forensic drug chemist routinely examines unknown white powders for the presence of controlled substances such as cocaine, heroin and methamphetamine. Sometimes the white powder is determined to be a common non-controlled substance found in most household kitchens.

In this experiment you will perform a series of tests on some of the white powders commonly encountered in the crime laboratory. You will distinguish each of the powders based upon the differences in physical and chemical properties.

· Download the Forensic Drug Chemistry and White Powder Identification Experiment.

· Complete the experiment.

· Report your results in the Unit 8 Matrix.

Forensic Fingerprint Analysis

Discussion

Answer each question with 250 word minimum

Touch DNA-You have studied some difficult surfaces for obtaining latent fingerprints in past units. What type of surface may be difficult to obtain touch DNA from? How would the environment affect this fragile evidence?

Collecting Fingerprints from a Weapon-Describe how you would collect a fingerprint from a weapon that could possibly have touch DNA on it as well. How would you collect the possible DNA? Which would you collect first?

Seminar

To receive credit for the Seminar if you are unable to attend write a 300-500-word paper on the Seminar topic below.

Touch DNA Analysis

This week's Seminar examines the newest technology breakthroughs in reference to touch DNA analysis as well as some case studies that involved testimony regarding the advent of this science.

Forensic Drug Chemistry and White Powder Identification

In this experiment you will perform a series of tests on some of the white powders commonly encountered in the crime laboratory. You will distinguish each of the powders based upon the differences in physical and chemical properties.

Materials

baking soda

table salt

corn starch

granulated sugar

eyedropper

iodine solution

vinegar

water

measuring spoon set

black construction paper

silver or white marking pen

white cups or small white bowls

hand magnifier or preferably a pocket microscope

Note:

The eyedropper and iodine solution are readily available in most pharmacies.

The eyedropper must be carefully cleaned prior to performing each different test. The measuring spoons must be cleaned prior to the sampling of each powder.

You will be able to observe the appearance of the powders better with a pocket microscope than with a hand magnifier.

Procedure:

Place ½ teaspoon of each of the four white powders on a separate sheet of black paper.

Test # 1

Take your eyedropper and add a drop or two of warm water on to a portion of each of the powders.

Test # 2

Using your eyedropper, add about 10 to 15 drops of the iodine to about ½ cup of water and stir. The solution should look somewhat like a moderately dark tea beverage. Add ½ teaspoon of each powder to a separate small white bowl or cup. Using your eyedropper, add 1 to 2 drops of the iodine solution to the powders.

Test # 3

Place ½ teaspoon of each powder into a separate bowl or cup. Using the eyedropper, add 1 to 2 drops of the vinegar to the powders.

Directions

• Complete the Forensic Drug Chemistry and White Powder Identification Experiment.

• Record your observations in the Matrix.

• Submit the Matrix to the Unit 8 Dropbox.

Describe the appearance and general shape of each powder. Do any have a crystalline appearance?

Rub each powder through your finger and describe the texture. How does it feel? Describe the reactions observed in Test 1.

Describe the reactions observed in step Test 2.

Describe the reactions observed in step Test 3.

Baking Soda

Table Salt

Corn Starch

Granulated Sugar