In Fisher v. City of San Jose, 558 F.3d 1069 (9th Cir. 2009) (en banc), the Ninth Circuit held that a twelve hour armed standoff that started with an exigency continued with one, and the police were not required to assess the situation minute-by-minute to determine that they needed an arrest warrant:

According to Fisher, the only reasonable conclusion supported by the evidence is that the exigency that existed before 6:30 a.m. dissipated after that time, thus rendering his continued seizure and the completion of his arrest unreasonable under the Fourth Amendment. Implicit in Fisher’s argument is the following premise: in an armed standoff, once a suspect is seized by virtue of being surrounded and ordered to surrender, the passage of time may operate to liberate that suspect, re-kindle the arrest warrant requirement, and require police to assess with each passing minute whether the circumstances remain exigent.

We reject this premise. Not only does it buckle under the weight of Supreme Court caselaw and that of our own circuit, but it further complicates the already complex and dangerous process of safely resolving armed standoffs, without providing any meaningful Fourth Amendment protection. We conclude that once exigent circumstances and probable cause justified Fisher’s seizure, police were not required to obtain an arrest warrant despite the fact that they did not take Fisher into full physical custody until hours later.

. . .

Requiring police in this type of siege environment to obtain an arrest warrant for Fisher, a person who is already under arrest but not yet in full physical custody, serves no practical purpose. Given that police had ample probable cause to arrest Fisher for felonies committed in their presence, any warrant obtained by the police would have merely authorized them to do exactly what they were already doing, and indeed, exactly what they were already authorized to do: surround Fisher’s home and attempt to neutralize the threat that he posed by arresting him. We do not see what a neutral and detached magistrate would have added in helping to peacefully effect Fisher’s arrest. Fisher is unable to clearly define what the Fourth Amendment allegedly required (or should require) the police to ask of the magistrate judge in the instant case. There is no support for the position that, after Fisher had been lawfully seized in his apartment, the Fourth Amendment required the police to retroactively justify the arrest to a magistrate judge by asking for an arrest warrant that had in effect already been executed. In fact, asking the magistrate judge to determine whether probable cause justified the initial seizure when police first surrounded Fisher’s residence or justifies his continued seizure amounts to the retroactive warrant practice that we have condemned. See United States v. Allard, 634 F.2d 1182, 1187 (9th Cir. 1980) (observing that “post hoc justifications [for searches and seizures] are alien to the Fourth Amendment warrant and reasonableness requirements”).

In addition, Fisher’s dissipation theory would have serious consequences beyond simply forcing police to engage in the empty gesture of obtaining a warrant in the midst of a dangerous and volatile standoff. It would introduce yet another element of uncertainty into the already complex and dangerous calculus confronting law enforcement in armed standoff situations. At minimum, the officers on the scene would be unable to devote their full attention to the actual threat and to ensuring public safety. Police would be forced to ponder with each warrantless arrest that existed at the start of the standoff had sufficiently dissipated such that they must immediately divert one or more officers from the task of resolving the standoff to the time-consuming project of obtaining a warrant. As we have recognized, “[o]btaining a telephonic warrant is not a simple procedure; among other things, a duplicate original warrant must be prepared in writing and read to the magistrate verbatim. The only step that is saved is the trip to the magistrate’s office.” United States v. Good, 780 F.2d 773, 775 (9th Cir. 1986) (internal quotation marks and brackets omitted).

One dissent argues:

The majority’s contention that requiring a warrant in the circumstances presented by this case would be pointless and inefficient suggests that today’s opinion has less to do with the conduct of Fisher — whose drunken interaction with a security guard led to a twelve-hour, hostage-free standoff; a single misdemeanor conviction; and an award of nominal damages and additional police training — and more to do with the majority’s lack of respect for the warrant requirement. This court is not free to abandon that requirement, and it is regrettable that the majority renders it a nullity in the category of cases before us. It does so without any precedent in law, and its sole legal rationale consists of an erroneous extension of a single Supreme Court case — a case designed to allow emergency efforts by firefighters to eliminate unsafe fire conditions — to circumstances in which it has absolutely no applicability. Even more regrettable is the majority’s failure to respect the historic Fourth Amendment principles that give meaning to the warrant requirement. Accordingly, I dissent.

Comment: This is another example of hard cases make bad law. A standoff is sui generis, and making the Fourth Amendment fit once the exigency starts and then allegedly dissipates is difficult at best. Both sides have their points, but, once the suspect has started the standoff, he should be in no position to argue that an arrest warrant was really needed as the standoff become less exigent. A sliding scale just will not work in this type of case, because requiring an arrest warrant adds nothing to protect the rights of the accused in this situation.

Law.com's story is here. The panel decision from November 21, 2007 is posted here.