"Its Him!" (SPOILERS)
There seems to be agreement that the ending of Cutter's Way is ambiguous in that classic 70's way(here, in 1981).
But one bit of ambiguity I like that is "within" the greater ambiguity is how Bridges yells out to his dying friend Heard, "Its him!" (maybe even saying "he did it!") as Heard dies.
We can figure at least two things going on here :
ONE: Bridges wants to make sure that his dying friend BELIEVES they have the right man, that his death is not in vain. So Bridges reassures him, as if to say "You weren't wrong, its him, and I'll avenge you." (I believe Heard is already dead by the time Bridges puts the gun in Heard's hand and pulls the trigger.)
TWO: But maybe also, Bridges, who has been "cagey" about whether or not Cord is actually the man he saw, realizes that he has to DECLARE what he DOES know: its him. He always knew, deep down, exactly who he saw.
Cord adds to the certainty by first putting on his sunglasses(makes him look more like the man Bridges saw) and by saying
"And what if I did?"
A challenge: "I did it, and you can't prosecute me." OR "I didn't do it, but it doesn't matter, I'm a powerful man anyway."
A lot going on in that last minute...but I do think that Bridges putting the gun in Heard's hand allows Heard his vengeance...and Bridges the opportunity to blame Heard for the killing.