One does not have to be a policeman to serve on a jury where a policeman is charged of murder. In fact, policemen would not be permitted to serve on such a jury, and for good reason.

It is certainly true that we do not have all the pertinent facts in this case. And it is not our jobs to pass judgement, in any case.

However, it is not typically held that having a bad time of things gives you permission to break the law. Even if you are having a very very bad day. It may modify the charge from murder to manslaughter. And it may affect sentencing. It does not give you a get-out-of-jail-free card, though.