> the police do not decide which laws to ignore and which to enforce

They absolutely do. For example, police in Seattle explicitly made marijuana enforcement the lowest possible priority years before Washington legalized it. It was a common sight to see policemen standing right next to people openly smoking pot on the street and completely ignoring them.

The police actually have a huge amount of leeway, and it can be a big problem. They often decide who to prosecute and who to ignore, and their decisions are often driven by race, revenue concerns, or other issues that have little to do with justice.

Actually, in 2003, the voters passed an initiative mandating that police lower their enforcement of marijuana in Seattle[1].

[1] http://www.seattlepi.com/local/article/Two-years-later-littl...

That's true, but marijuana was still illegal, and some people were still prosecuted. Ultimately the ones deciding who would be arrested and who would be ignored on a case-by-case basis were the police.

You're correct. My point was directed more towards people, like the parent I was replying to, who defend government actions simply because something is illegal. It would be equivalent to defending people who returned escaped slaves back in the day because it was the law to do so at the time.

Which would you rather have? Police enforcing the laws, or police enforcing whatever they personally felt was right?

If you disagree with the morality of a law, fine - but your assertion that enforcing drug laws is as immoral as enforcing slavery laws is debatable

Actually, they do. http://thelawdictionary.org/article/police-discretion-defini...

Police officers can, and should, use their conscience to decide whether or not to enforce certain laws.

If you want a legal precedent, the Nuremberg trials somewhat settled that question.

Well, the likely continued impunity of the practitioners of "enhanced interrogation" means that it's a legal precedent that applies only to evil Nazis.