He’s planning to appeal, and he’s not yet gone to jail. But I don’t know what his grounds for appeal are; the case seems pretty clear-cut. The injuries he sustained strongly suggest he was at the wheel of the boat when it crashed, while his friend, who died, had injuries suggesting he was the passenger. I’m just translating from the Finnish stories I’ve read, because I’m sure the majority on here don’t understand the language.
It appears that both JJ and the prosecutor are going to appeal the decision, neither party are happy with the current situation. The case will now go to Hovioikeus (http://en.wikipedia.org/wiki/Hovr%C3%A4tt), the second highest judicial body in Finland. No news when and how long it’s going to take, but my guess is at least six months.