What is the good faith defense to an invalid warrant?

Law enforcement is, at its core, based on a framework of authority directing those bound to follow that authority. It would cause a lot of inefficiency and confusion if we expected every police officer to critically analyze every order they were tasked with executing. Don't get me wrong — there are obviously some times that police are required to use some level of critical thinking (and we'll talk about those situations in a little bit), but in general the law gives officers the benefit of the doubt that they were acting with good faith when they executed a warrant. What does this mean practically? It means that if a warrant is technically invalid, but the police officer executing it had no reason to doubt its validity, then the law isn't going to throw out evidence that is secured as a result of executing that faulty warrant.

For example, imagine if Bob's county had mistakenly issued an arrest warrant for Bob but realizes their mistake and sends a note to the clerk to delete Bob's warrant from the system. Unfortunately, the clerk fails to do so and the warrant remains in the system. Later that day, Officer sees Bob drive by and, when he searches his license plate in his system, Bob's arrest warrant pops up. Officer pulls Bob over, arrests him, and searches Bob's car where Officer finds a large block of crack cocaine and illegal firearms. Here, the drugs and weapons were technically discovered only as a result of an invalid arrest warrant and you may think that the exclusionary rule would apply. However, because the Officer executed the invalid arrest warrant in good faith that it was valid, the law will allow the evidence found during this search to be admitted and used against Bob. If you think this seems unfair, that's reasonable: the rule comes from Herring v. US, which was decided 5-4 by the 2008 SCOTUS.

With that rule in mind, let's talk about the exceptions that effectively destroy the "good faith" argument:

The first exception is when the officer should have known the warrant was nonsense because its affidavit was severely lacking in probable cause or in how it described what was being sought. In other words, a valid warrant will contain a written statement submitted under penalty of perjury that provides guidance as to why the warrant is being issued and how it should be executed. If this affidavit is gibberish, or if it fails to explain the terms of the warrant (who is to be arrested, or what property is to be search and/or seized), then an officer is expected to seek clarification or validation of the warrant and not simply blindly follow its authority.

The second exception is a bit more obvious: if an officer or government agent lies to a judge/magistrate in order to get the judge to approve their warrant, then they obviously lack good faith, and thus there is no good faith defense.

The third exception occurs when there is evidence that the judge/magistrate has failed to maintain their neutrality and has "wholly abandoned their judicial role," meaning they no longer stand for justice.