The Pennsylvania Supreme Court recently delivered a ruling that forbids police from taking a blood sample to test for DUI from an unconscious suspect. The decision is not surprising because it appears to parallel U.S. Supreme Court decisions in drunk driving cases. It is a Fourth Amendment violation for authorities to conduct a search in that manner.
It is also tantamount to compelling an individual to relinquish the privilege against self-incrimination by forcing a blood test without consent. The state has an implied consent law that implies that a drunk driving suspect has given consent. However, the individual can refuse consent under penalty of losing his or her license for a specified time. That is a common statutory pattern seen in most state DUI laws and driver's licensing regulations.
In the reported case, the police arrested a man for suspicion of drunk driving in Dec. 2012. The operator was driving erratically, according to the police. They pulled him over and observed slurred speech and the odor of alcohol on his breath. After the arrest, the suspect was taken to a hospital where he passed out after receiving medication. The officer could not communicate with him, and he consequently directed the hospital staff to draw a blood sample.
The defendant later filed a motion to suppress that sample. That motion was granted by the lower court and affirmed by the Superior Court. The Pennsylvania Supreme Court affirmed the Superior Court's decision. The decision did not rule out taking blood in that situation, but the courts made it clear that the officer could have obtained a search warrant prior to drawing blood. The warrant would have reasonably issued if the authorities could show probable cause of drunk driving, which was established by virtue of the observations of police before and after stopping the suspect.
Source: fox43.com, "PA Supreme Court: Police must obtain search warrant to draw blood from unconscious DUI suspects", Sean Naylor, July 19, 2017