In the event either party in a divorce alleges drug abuse on behalf of the other party when there are children involved, the court can order drug testing.  Drug testing can be ordered by the court based on a request by either party or both parties and the court can order drug testing based on its own findings absent a request by either or both parties.  In most cases the court will require both parties to a drug test.  However, the requesting party will be required to pay for such a test upfront.  If the test results of the other party are positive then they will be ordered to reimburse the requesting party for the cost of the test.  IF they are negative, the requesting party will pay for the test.  If the court orders the test absent a request from either party, the parties will pay for their own test.  Never request drug testing if you are not reasonably sure that the other party will test positive because the court does not like “witch hunts!”
If you believe that your spouse or former spouse is abusing drugs you should request that the court order random drug testing.  Usually, the other party will always agree to random testing because to oppose it would give the appearance that they have something to hide.  Then the best procedure is to wait until a Friday or Saturday night or a time when it is likely they will indulge.  The following morning, have someone other than you contact the person to be tested and inform them they have 48 hours to test.  Failure to comply with any request for testing will likely be considered a “dirty” or positive test.
When requesting drug testing, be aware that there are three types of tests available – blood, urine and hair follicle.  Hair follicle is the most accurate as it can detect drug presence up to a year preceding use.