This is an extremely powerful film, made by a director who, in a very different way from Godard, sets out to demonstrate what cinema can do. The portrayal of violence is disturbing and unfamiliar because it is honest - as opposed to gratuitous or stylised - an approach which grounds the act of killing in the real world, hence the name.
Conversely, after watching this film the portrayal of killing in many other films becomes repulsive in its dishonesty, in its justification or condemnation of killing via a dualistic 'good/bad' morality. Kieslowski makes little attempt to justify or condemn either killing, but describes each in a detailed, almost matter-of-fact way. The viewer is left to apply her own morality to what she sees.