The Supreme Court has long maintained that police can not forcibly enter someone's home without a warrant on the suspicion of driving under the influence, but a federal appeals court recently upheld a case in which a Virginia officer did just that.
On October 3, 2004, Alan J. Cilman had dinner at a local restaurant where he drank and watched a football game. When he left the establishment, officer M.A. Reeves saw Cilman take off at a high rate of speed and proceeded to follow the sports fan to his home. Reeves claims that Cilman ran a stop sign, didn't use his turning indicators and accelerated quickly from each turn.
It's unclear whether Reeves actually activated his cruiser's lights while following Cilman. What is clear is that Cilman made it to his home and quickly walked to his front door while Reeves told him to stop, but did not say that he was under arrest. Cilman then locked his door and told the officer to get off of his property. Reeves called for back up, proceeded to kick in Cilman's door and arrested him for being drunk in public and evasion without force. Those charges were later dropped when a U.S. district court found that entering Cilman's property without a warrant was a violation of his Fourth Amendment rights.
Reeves then proceeded to appeal the decision. Virginia state law declares that if he were later found guilty of a another constitutional infringement, he would be removed from duty. The appellate judges decided that there is no precedent protecting someone from warrantless entry in a case like Cilman's. The court reversed every decision in Cilman's favor and dismissed the case entirely.