Everything they did outside the scope of the Warrant was a Felony Armed Robbery and they should all be prosecuted, just like everyone else
At present, our only solution as citizens is to ignore anything presented by the FBI/CIA/NSA/BATFE. As a juror, give it zero weight as evidence.
Frankly, at this point if an FBI scumbag is shot in the head by a homeowner upon presenting his 'credentials', as a member of a jury, I would consider it justifiable homicide even if the entire event was captured on camera. I honestly do not care if the person who killed the fed was a scumbag who belongs in jail. I honestly do not care about the death of anyone who works for the feral government at this point. Not one bit. Not one single tear.