Scenario 1

You are part of a legal partnership. Your client was required to take a drug test by her employer. The test came back positive. Your client insisted that she had not used any illegal drugs. She then took a second drug test in the hopes of proving that she was not a drug user. It, too, came back positive. She was fired by her employer and now faces charges related to drug usage.

• Include the detailed report of the probabilities of one, two, and three false positive results to drug tests. Use 7.5% for your false positive rate.

Scenario 2

You work for the Federal Aviation Administration (FAA). Your team is investigating the emergency crash landing of a commercial airliner. Fortunately, the plane landed safely. There were many injuries but no casualties. Naturally, the pilot must be tested for drug and alcohol use as part of the investigation. The pilot, unfortunately, did abuse certain substances which should have been detected by standard drug testing procedures and which would certainly impair his ability to fly safely. Your investigation protocol requires at least one test, with an optional second and third drug tests if needed, when preceding tests are negative for drug use. Why would the FAA require up to three tests?

• The pilot's three tests all indicated no drug usage, and he will be flying again within a month, after his crash related injuries heal.
• . Include the detailed report of the probabilities of one, two, and three false negative results to drug tests. Use 12.5% for your false negative rate. Cite your resources.
• You have been advised by a very credible source that the pilot is, indeed, abusing substances that will impair his ability to do his job safely in the future, but you do not have the proof based on the drug tests.
• What will you say to try to ensure the safety of his future passengers?