A cop kills a man in his own apartment. Says she mistook it for her apartment. Did she have a key? How did she get in? Was she DRUNK?

No key, not drunk. The door was ajar, saw a large siloette and thought he was a burgular and shot him thinking she was in her apartment. 

She will likely be charged with manslaughter. 

All of the decisions made by an officer in two seconds will be picked apart, analyzed and reconstructed, misconstrued, misrepresented, replayed and argued in court, for a minimum of two years after the fact. Right, wrong or something in between, that's the reality of any and all incidents where deadly force is used.