Jacob Sullum writes:

Hudson v. Michigan, the recent decision in which the Supreme Court said evidence from a search in which police failed to follow the “knock and announce” rule is admissible in court, ostensibly hinged on how close the connection between a Fourth Amendment violation and the discovery of evidence must be to trigger the exclusionary rule. The dissenters argued that the failure of police to wait more than a few seconds for the suspect, Booker Hudson, to answer the door rendered the whole search invalid, making the evidence police obtained “fruit of the poisonous tree.” Writing for the five-justice majority, Antonin Scalia said the exclusionary rule did not apply in this case because the Fourth Amendment violation was not essential to the discovery of the evidence. Had police waited, say, 15 seconds and given Hudson the opportunity to answer the door, Scalia reasoned, they still would have found Hudson’s drugs and gun.

Yet as Scalia also noted, if the police believed that wasn’t the case, that waiting 15 seconds would have allowed Hudson to get rid of the evidence, the “knock and announce” rule would not have applied. So the nexus between barging in and finding the evidence does not really matter. Whether or not a knock-and-announce violation is necessary to preserve evidence, the evidence can be admitted — an easy rule for police to remember but not one that is likely to encourage respect for the knock-and-announce requirement.

This is one of the inherent contradictions in the policy of no-knocks and the use of SWAT teams.

After Wilson v. Arkansas, in which the Court ruled that the Fourth Amendment generally but not always requires police to knock and announce themselves before entering a private home, several states passed laws requiring announcement, banning no-knock warrants issued from the bench. Since Hudson, there’s some talk that yet more states will pass similar laws (Indiana is considering it, for example). But these laws are meaningless, for a couple of reasons:

First, the “exigent circumstances” exceptions still allow police to decide at the scene to enter without announcement if they think the suspect will dispose of the drugs, or that he poses a threat to police. Before Hudson, whether or not the police made the right call was determined after the fact, at trial. (If they found nothing incriminating, the entire raid was chalked up to “oops,” except in the rare case where the person on the receiving end of the raid brought suit.) After Hudson, there’s little reason to make such an after-the-fact evaluation, given that the evidence will be admitted either way.

Second, defenders of SWAT teams and dynamic entry tactics say they’re necessary to take suspects by surprise. This, they say, prevents violence. I’d argue it encourages violence and confrontation, but for the sake of argument, let’s say they’re right.

But the same people say that Hudson won’t really change anything. Police will still observe the rule, and knock and announce before entry. But the purpose of the knock-and-announce rule is to give the suspect the opportunity to answer the door, and avoid the destruction of property and violence of a forced entry. You can’t have it both ways. You can’t say we need SWAT teams to take suspects by surprise, but that most SWAT teams are also observing the letter and spirit of the knock-and-announce requirement.

That requirement is to give notice and opportunity to answer. And that, of course, is incompatible with “surprise.”

This is illustrated by the fact that these raids are commonly conducted late at night, or very early in the morning. If you’re asleep — perhaps in an upstairs bedroom — and police knock and announce just seconds before breaking in, for all practical purposes the difference between “no-knock” and “knock-and-announce” is nil.

But don’t take my word for it. California has had a law against no-knock warrants for some time. After a 1999 dynamic entry raid in which El Monte police shot and killed Mario Paz — an innocent man — the assistant chief of police told the Los Angeles Times: “We do bang on the door and make an announcement — ‘It’s the police’ — but it kind of runs together. If you’re sitting on the couch, it would be difficult to get to the door before they knock it down.”

I’ve been outspoken on the Hudson case. But the truth is, it’s a peripheral issue. The main problem here is not no-knock raids, legal or otherwise. The main problem is the paramilitary tactics, and this relatively recent fervor to break down the doors and storm the homes of suspects who, even if guilty of what’s suggested in the warrant (generally drug crimes), aren’t an immediate threat to the public, the community, or anyone else.