It is just a nightmare procedurally.
You probably haven't been following it, but I am a casual NASCAR fan and my favorite driver growing up was Jeremy Mayfield. A week ago Mayfield was the first big driver to be caught in NASCAR's drug testing scheme. Mayfield has claimed it was a mix of over the counter and prescription drugs, but NASCAR is indefinitely suspending him without telling him or the public what the offending drug was. NASCAR's drug testing policy, implemented in the absence of a driver's union, is harsh and secretive. But, because it is harsh and secretive, when it ruins a driver's career like Mayfield's, it is almost guaranteed to be challenged in court. NASCAR allowed Mayfield to race after testing positive on the first sample, so it is questionable just how dangerous Mayfield was, if at all, on the track. And, now that they have caught him, they are probably looking at hundreds of thousands of dollars defending their actions.
As education moves closer and closer to randomly drug testing teachers (2), we should learn a lesson from NASCAR here. NASCAR is a billion dollar sport with virtually unlimited resources to test their small cadre of privately employed drivers and crew ... and their drug testing scheme is a procedural nightmare and may well wind up an embarrassment when this hits the court system. Schools, with limited resources and public, frequently unionized, employees, is going to be even a harder drug testing system to procedurally manage and it will have to be done with far fewer resources. Implementing teacher drug testing systems is going to be a nightmare for schools procedurally and state officials need to really consider whether it is worth that cost.