A good heuristic is to always favor the long term over the short, unless doing so significantly endangers the long term from ever coming to fruition. Of course,

A good heuristic is to always favor the long term over the short, unless doing so significantly endangers the long term from ever coming to fruition. Of course, "significant" is subject to discussion. A serial killer, no matter how dangerous, has near zero chance of taking down the government and legal system, so to preserve the precedence for good policing practices, the judge should throw the evidence out. After all, if said person is actually a serial killer, there will be more chances to catch them properly. In general, I'm willing to sacrifice a few people (including the people I love the most) to preserve just and fair institutions, but not the other way around.