Watson, founder of Sea Shepherd and co-founder of Greenpeace, has been arrested on an international warrant and is facing charges including accomplice to assault and ship trespass
It's not 100% but it's super high and, yeah, they usually don't prosecute unless they think they have a really solid case. That said, some of that also includes confessions that some have argued are under duress (and, in the case of foreigners, people who aren't exactly sure what they're signing, though I have no idea how that's legal).
They also can hold suspects in detention without trial or hearing for months while they investigate, if they choose. It's not often discussed but it's a huge part of the pressure/duress.
This may have changed since I learned about it in 2008, but my understanding is that they get around that rule by technically "releasing" you and "rearresting" you on suspicion of related crimes. The "rearrests" can stack.
I think it has to be another crime, but that probably still can be done. I'm not a lawyer so I'm not sure, and I hope I never have occasion to find out.
Not sure what sort of sentence he's looking at here though.
The guy who actually boarded the ship and tried to assault the captain only got a suspended sentence. And this guy is being tried as an accomplice for that.
So I've also heard. But first Denmark must extradite him, which I doubt they will do.
He has a horde of followers who has quite good at internet warfare. So any action against him would be a political shit storm. Denmark is undoubtedly being pressured from all sides to release him.