Brock Hopkins acknowledged smoking pot before arriving to work at Great Bear Adventures on Nov. 2, 2007. When he entered the bear's pen, he was attacked and had to be hospitalized.
The owner of the attraction near Glacier National Park says Hopkins was a volunteer and that his use of marijuana caused the accident.
But Judge James Jeremiah Shea of the state Workers' Compensation Court ruled last month that Hopkins is eligible for benefits.
Shea found that Hopkins was paid, and therefore he's an employee. The judge also concluded Hopkins' use of marijuana was not the main cause of the attack.