Jigsaw is in fact a murderer.

In Saw 3 he elaborates that he doesn't condone murder and he despises them.

But in Saw 1 he clearly violates that.

Adam was given a key to escape in the bathtub but he was never told about the game or his chance to escape. The key was set up in a way in which he would most likely lose in the drain.

When Jigsaw wakes up at the end, he walks out and closes the door leaving Adam to die a slow death of hunger, dehydration, or from the gunshot wound.

So...as Jigsaw he orchestrated Adam's kidnapping, had him chained to a room, then locked him in to die. That is pretty much premeditated murder so Jigsaw is a hypocrite when he punishes Amanda for being a murderer even though she clearly deserved it too.