Last week, the Ninth Circuit handed down an amended opinion in United States v. Al Nasser that raises a fascinating and rather difficult Fourth Amendment question: Is a person "seized" for Fourth Amendment purposes if he reasonably thinks an officer is trying to stop him, and he stops in response, but the officer is actually trying to stop someone else? In the case, officers had pulled over some other cars for violations, and had their lights on, and the driver of a car apparently thought he was being pulled over, too, even though he wasn't. Here's the question: Assuming, for the sake of argument, that the driver reasonably thought that he was being stopped, and that he stopped as a result of it, was the stop a seizure if no officer actually intended to stop that car?

  The Ninth Circuit concludes, in an opinion by Judge Kleinfeld (joined by Trott and R. Smith), that no seizure occurs in such a situation. I tend to think that is correct, under Brower v. City of Inyo, but it's actually a pretty difficult question. Unfortunately, I don't have time to blog all the complexities, but I did want to flag the opinion for readers interested in such a fun Fourth Amendment issue.

  Thanks to Lee Rudofsky for the tip.

  UPDATE: Some commenters think that the decision is wrong under Brendlin, but remember that in Brendlin the officer knew he was bringing that car and all of its contents to a stop and did bring the car to a stop. Also, note that if the result in this case is wrong, then an officer presumably violates the Fourth Amendment when he turns on his siren in traffic and it's not clear who he is stopping. If anyone stops out of reasonable confusion over whether he is the one the officer is trying to pull over, even if only temporarily, then the Fourth Amendment rights of the confused driver and all of his passengers are violated based on the misunderstanding. That seems like an odd result to me -- not impossible, but odd.