Did the US violate its own law and international law by tipping of Saudi Arabia?

It seems that the US tipped off the Saudi regime to order the Lebanese Security Services (a militia run by Hariri family and funded by Saudi Arabia and US and is playing a big role in repressing the Lebanese people) to arrest a Saudi dissident (who is accused by Saudi regime of involvement in the Khubar bombing).  Even if he is guilty (and he has not been tried), the US government led to his arrest by a government that beheads.  Is there not an American law against surrounding a wanted man to a government that does not even have a semblance of rule of law, as the recent report by Amnesty International indicated?