A number of American suspects in high - profile cases have not been brought to justice , say Italians . In 2006 , 20 people were killed when a U.S. Marine Corps jet sliced through steel wires supporting a cable car in the Italian Alps . In 2009 , American soldiers opened fire at a Baghdad checkpoint , killing Italian secret service agent Francesco Calipari . Suspects are not required to attend court hearings in Italy , so Knox does not need to return to stand trial , at least in the short term . The trial of Seattle student Amanda Knox , accused of killing her British roommate Meredith , is also controversial .
A number of American suspects in high - profile cases have not been brought to justice , say Italians . In 2006 , 20 people were killed when a U.S. Marine Corps jet sliced through steel wires supporting a cable car in the Italian Alps . In 2009 , American soldiers opened fire at a Baghdad checkpoint , killing Italian secret service agent Francesco Calipari . The trial of Seattle student Amanda Knox , accused of killing her British roommate Meredith , is also controversial .