The police probably found him holding the gun De Silva stupidly grabbed from a park security guy Chucky had murdered just a couple of minutes ago, so I find it pretty hard for Andy to come up with a very convincing explanation that leaves him free of charges.

They probably also find De Silva's fingerprints on the gun as well, she will heal her surgeries in prison...

I love this movie thought, as a story, it's well structured, the problem resides in the fact that it had a horrible transformation from script to screen. it was poorly captured by the director.