Civil asset forfeiture — police confiscating the stuff of someone accused of a crime, on the theory that it might have been used in the crime or bought with money from it — is one of those widespread practices that get more controversial the more people pay attention to it.

A couple of states have passed laws dramatically restricting police's ability to confiscate property before the owner is actually convicted of a crime. In Congress, a bill has been introduced that would make sure people whose property is confiscated by federal law enforcement agents get a hearing to contest the seizure.

So it's not surprising that law enforcement agencies are on the defensive about it. After all, a significant revenue stream of theirs is under attack. But this, from the organization representing prosecutors in Pennsylvania, is probably not the best way to respond:

Civil forfeiture takes the tools of crime and turns them into tools for community safety. — PDAA & PDAI (@PennsylvaniaDAs) May 23, 2016

Here's what this tweet is supposed to mean: Civil forfeiture takes, say, money that would otherwise be used to commit crimes and puts it toward funding community safety. The Pennsylvania District Attorneys Association has used versions of this line before that make this clear: "Forfeiture takes the tools of crime, such as cash proceeds, cars, computers, real property, and technology into custody so the crime can no longer be committed," the association wrote in testimony to the state legislature last fall.

Here's what I thought the tweet meant the first couple of times I read it: Stealing other people's stuff is a crime when someone else does it, but it's "community safety" when police do it.

That's a blunt statement, but it's not an unfair one. On some level, that's the basic assumption on which civil asset forfeiture rests.

If you think it's a good and acceptable thing to take someone's assets before she's actually convicted of anything, and make it difficult (if not impossible) for her to retrieve them, even if a conviction never comes, you're accepting that some people who (in the eyes of a court of law) have never committed any crime are going to have their stuff taken away from them anyway. If you weren't okay with that sort of false positive, you would either support waiting until after conviction to confiscate property or support automatic restitution for anyone whose charges are dropped or who is found not guilty.

Here's the thing: There are a lot of law enforcement tactics that if you dig into why police feel justified in doing them, you eventually run into the principle of, "If you do it, it's illegal; if law enforcement does it, it's public safety."

Obviously this applies to the core parts of the job (making arrests and detaining suspects, for example). But there are plenty of tactics that law enforcement officers use that are not just legal but are considered good law enforcement practice, even though they'd be blatantly illegal if they didn't come under the "color of law."

Encouraging someone to commit a terrorist act and helping him plan it or obtain supplies is usually considered incitement or conspiracy. But if a law enforcement informant befriends someone after seeing him post things about "waging jihad" on social media, tells him what he needs to do to buy a bomb, and gives him a map of a Kansas military base — an actual description of a 2014 terrorism "sting" — it's a useful law enforcement operation to catch a would-be terrorist.

If you pose as a 16-year-old girl and start flirting with adult men on the internet, it's catfishing at best and fraud at worst; if police do it, it's a pedophilia sting. If you lie to a police officer during an interrogation, it's (under many circumstances) a crime; if the police officer lies to you, it's (under most circumstances) considered good interrogation technique.

Well-informed people can disagree about which of these practices are really necessary, and under what circumstances. But those disagreements would be a lot more honest if people owned up to the principle that some things are simply okay when they're being done in the name of public safety.