Spain Investigates What America Should

"A Spanish court has initiated criminal proceedings against six former officials of the Bush administration. John Yoo, Jay Bybee, David Addington, Alberto Gonzales, William Haynes and Douglas Feith may face charges in Spain for authorizing torture at Guantánamo Bay.

If arrest warrants are issued, Spain and any of the other 24 countries that are parties to European extradition conventions could arrest these six men when they travel abroad.
Does Spain have the authority to prosecute Americans for crimes that didn't take place on Spanish soil?
The answer is yes."