In an internet chat room last May, the 46-year-old had threatened to shoot former Prime Minister Matti Vanhanen and Finance Minister Jyrki Katainen and to blow up the House of Parliament.
The defendant said the comment was made on impulse after watching parliamentary question time on television, and was not intended to be read by the politicians.
The court ruled on Tuesday that the comments were a general expression of frustration rather than a specific threat, and there was no evidence they had caused any danger or fear.
National Police Commissioner Mikko Paatero criticised the decision, saying that it opens the door for further threats of this kind.
"If this verdict is the conclusion on the matter, the law needs to be changed," he stated. "Or then, hopefully, we'll see after the Court of Appeal has handled this case."
In December, a court fined a man who posted threats against Migration Minister Astrid Thors on Facebook. The defendant also forfeited his computer to the state. The former local True Finns politician was found guilty of aggravated slander and making illegal threats.
