No more need to demonstrate probable cause. No more need to persuade a judge to sign a warrant. No more annoying criminal defense attorneys litigating the Fourth Amendment.
As the law stands today, a police officer may request a sample of a driver's breath or blood if there is probable cause to believe the motorist is driving while intoxicated. The motorist is free to decline the officer's request and risk having his driver's license suspended. The law authorizes a forced blood draw in the event there was an accident and another person with either killed, is expected to die or suffers a serious bodily injury.
If the driver refuses the officer's request for a breath or blood test, the officer may force the driver to submit to a blood test if a judge (at the county court level or higher) signs a warrant authorizing the blood draw. Those warrants, however, are subject to litigation regarding their validity.
Come September 1, an officer may require a motorist to submit to a blood test in any accident in which anyone is injured, regardless of the severity (or lack thereof) of the injury. In addition, any judge or magistrate (which would include municipal court judges) who is a licensed attorney, will be authorized to sign a blood warrant in a DWI case.
These changes, along with prosecutors forcing defendants into pretrial diversion programs in Harris County, just serve to illustrate the erosion of constitutional protections for those suspected of driving while intoxicated.