I think some people have the view that judicial systems outside of the US are kangaroo courts. I saw the movie La Scorta, which was about a bunch of bodyguards for Italian magistrates in charge of cases against Cosa Nostra kingpins. My impression then was that Italy mollycoddles criminal suspects. Its justice system is anything but draconian and arbitrary.
Or worse, result in guilty people going free: http://www.nj.com/opinion/index.ssf/2014/04/spare_us_the_lies_about_the_late_hurricane_carter_mulshine.html
The Double Jeopardy clause became part of the Fifth Amendment because of endless abuses of an open-ended process by The Crown, not because one verdict of not guilty is always the best possible outcome there is. The Italian system is not an open-ended arbitrary process. It has well-defined steps and a definite conclusion. And most importantly, if it were really an affront to the Rights of Man Italians could change it. In fact, much more easily than we can.