I don't know... I don't normally nitpick artwork too closely and I always liked his... but based on what we can see of his upper arm... there isn't any comfortable way to move that arm/elbow where we aren't seeing it. I feel like we should be seeing his hand or his fingers somewhere back there... but it they weren't drawn in. Just an awkward pose all around.
From what I can see, his hand is probably behind Hal Jordan's deltoid. His arm bends at the elbow joint, which would be behind Black Canary, about close to where her boobs meet. For artistic clarity, it probably would have been better if the artist drew the hand where we can see the fingers on top of Hal Jordan's shoulder, so we know exactly where it is and what it's doing, but what the artist presented can be done. His hand is on Hal Jordan's back, out of view.