Some of them have a doubt, test results of any drug performed by drug test kits can be used as legal evidence. Results are used as legal evidence but if they are conducted through only few methods. For military testing samples of more than 300 people will be collected. On a paper every person who involved in collection of sample, packing them, etc will sign on it. The signed paper is treated as evidence that samples are collected properly and no tampering is done with specimens.
Breathalyzer, urine drug test, blood test are few drugs, which results can be used as legal evidence. Breathalyzers test is conducted to know the person who is driving the vehicle has consumed or not. This test is conducted on the road and if the person found as positive, he can go behind the bars.
Different methods used for drug detection after any incident, such results are used as main evidence. Post-incident drug testing is not commonly administered test. These test results can make them go behind the bars or even lose job, if results are positive.