Drug testing should not be mandatory in the workplace. One of the reasons for this is because Professor Leonard H. Glantz says that taking drug tests violates and sacrifices the citizen's 4th Amendment rights. The 4th Amendment guarantees protection from searches for the sake of the war on drugs. The 4th Amendment clearly states "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized." Most courts have concluded that a mandatory drug test can be considered as a search under the 4th Amendment.
Another major reason is false positives. A false positive occurs when a test indicates the presence of a drug when there isn't any drug being used. Dr. David Greenblatt of the Turfs New England Medical Center says, "False positives can range up to 25% or higher. The test is worthless." Dr. Kent Holtorf says that more false positives than accurate tests are reported by laboratories.
Cough syrups, nasal sprays, and eardrops show up as a false positive. One example is if you are taking a hair drug test, the more melanin in the person's hair, the greater the concentration of the illegal substance. Secondhand smoke from marijuana and crack cocaine is also taken up in a person's hair. Many different prescribed medications produce a positive test result for amphetamines. Another example is that a test may come out positive for marijuana if you ingest ibuprofen, which is found in medicines such as Advil and Motrin.
Most businesses often demand that employees take drug tests to test for the presence of drugs in urine. The employer has to watch the employee urinate. If the employer doesn't watch the employee urinate then the test is invalid.
