"Mr Marshall, by any token, was desperately unlucky and so by the same token, is we say, this accused,'' Mr Percy said in his closing address.
Crown prosecutor Amanda Forrester said there was no explanation for Schmidt's unjustified attack on Mr Marshall other than a fit of rage.
She likened the incident to picking up a gun, pointing it at somebody and firing, without checking whether it was loaded or in working order, then realising the safety catch is not on.
"He did not just push him towards the window, he pushed him at it, into it and through it,'' Ms Forrester said.
"He was like a coil, ready to spring and he sprung at Mr Marshall.''