There is a wide spectrum for how strictly "presumption of innocence" is followed in various societies in practice though.

The creator of the Winny filesharing program in Japan was dismissed from his Tokyo University Research Assistant position as he went to trial:

"On May 10, 2004, Kaneko was arrested for suspected conspiracy to commit copyright violation by the High-tech Crime Taskforce of the Kyoto Prefectural Police. Kaneko was released on bail on June 1, 2004. The court hearings started in September 2004 at Kyoto district court. On December 13, 2006, Kaneko was convicted of assisting copyright violations and sentenced to pay a fine of ¥1.5 million (about US$13,200).[3] He appealed the ruling. On October 8, 2009, the guilty verdict was overturned by the Osaka High Court.[4] On December 20, 2011, Kaneko was cleared of all charges after a panel of judges agreed that the prosecution could not prove that he had any intention to promote the software for illegal use.[5] [6]" (http://en.wikipedia.org/wiki/Winny#Criminal_procedure)

He was definitely treated by society as if he were guilty of the crime as soon as he was arrested.

By that standard, suspects are often presumed guilty by society even in the USA (for instance, suspected rapists and other sex offenders). The presumption of innocence is still considered one of the core principles of democracy and/or the rule of law.

Its a fair point, its much more codified elsewhere than it was at one time. And to be fair the US has been doing things like locking people in Guantanamo without due process which is disturbing in itself. The point I was trying to make clear was that I recognize trying to interpret a story involving the actions of a the police in a country which doesn't have the same legal climate as the one I live in, it fraught with dangers in making assumptions that don't or won't hold up.

'common law' countries, not 'democratic' countries.

Which would make my sentence: It's an accepted core tenet of all common law countries and many of the others. Well, I suppose that's still true! But I don't think the tie to common law is stronger than the one to the US; it's an almost universal principle.

My point is that it's a core tenet of the common law system, not a core tenet of democracy. Allowing your citizens to vote does not automatically mean that they have a presumption of innocence. It just means that they can vote.