Arrested for a dui, does court do drug testing before/after trail?

Yes, the court may order a drug screen as a condition of continued bond (release), or may order a drug screen, or even a breath test, on your day your case is scheduled for court. In my experience, I have had clients show up for court and test positive on drug charges or test with alcohol in their blood stream on court day. In such cases, the trial court will ordinarily find the defendant in contempt and order the defendant jailed. As a general rule, a court will not accept a plea or conduct a trial if the defendant tests positive for drugs or alcohol on the trial date or any other day where a proceeding is conducted. The trial court retains jurisdiction over the defendant until the defendant is either acquitted, or if convicted, until the term of the probationary period expires by law, or is ended by court order, or end of sentence.

It will depend on the court. They can make it a condition of continued bond. Every jurisdiction is different but my experience is that I see very few drug tests ordered by the court on DUI alcohol arrests unless there are signs of impairment when you are in court. (I handle approx 225 DUIs per year in Western OK). There are some constitutional arguments that can be made if the court is just ordering random drug tests without some type of suspicion. John Hunsucker

As both attorneys responses appear to be correct, I would contact a TN DUI attorney for the precise answer.