Provided they're the ones doing it, of course:
The US has told Britain that it is legal under US law to kidnap British citizens from the UK (ineed, anyone from anywhere) if they are suspected of crimes in the USA -- and that this can be done instead of using formal extradition procedures.Of course, given the current one-sided extradition arrangements between the US and UK (under which the US can demand a british citizen be turned over to them, without having to show any evidence whatsoever), they don't actually need to bother.[...]
[A US government lawyer] said that if a person was kidnapped by the US authorities in another country and was brought back to face charges in America, no US court could rule that the abduction was illegal and free him: “If you kidnap a person outside the United States and you bring him there, the court has no jurisdiction to refuse — it goes back to bounty hunting days in the 1860s.”