It seems likely that the House Intelligence Committee will soon #ReleaseTheMemo. According to press reports, the memo claims that the FISA application to monitor Trump campaign advisor Carter Page included information sourced from former British intelligence officer Christopher Steele "without adequately explaining to the judge that Democrats financed Mr. Steele’s research."

This is a scandal, the argument runs, because it means the application was fraudulent. Because Steele was funded by Democrats, his reports were just unreliable opposition research designed to make Trump and his associates look bad. And if the FISA application was based on Steele's unreliable research, and DOJ never told that to the FISA Court, then DOJ misled the court and the court should not have issued the warrant.

As a Fourth Amendment nerd, it seems to me that the premise of #ReleaseTheMemo is pretty dubious. The apparent idea is that the failure to adequately document the funding behind Steele's work is a huge deal and a fraud on the court. But as a matter of law, that seems pretty unlikely to me. When federal judges have faced similar claims in litigation, they have mostly rejected them out of hand. And when courts have been receptive to such claims, it has been because of specific facts that are likely outside the scope of the memo that will be released.

Here's the context. It turns out that there is lots of litigation on whether warrant applications need to discuss the bias of informants. Franks v. Delaware allows a criminal defendant to challenge a search warrant by arguing that the statement of probable cause that supported the warrants was fatally flawed. Maybe the officer who swore out the affidavit was lying about the basis for probable cause. Or maybe he recklessly included facts that he should have known were false. Or maybe–as is particularly relevant here–he intentionally or recklessly failed to include facts that the judge needed to know in order to pass on whether there was probable cause. Under Franks, a court will void a search warrant if the defendant can establish that the officer who swore out the warrant "knowingly and intentionally, or with reckless disregard for the truth" either included information that was false or excluded information that was true when that information was critical to the probable cause determination.

Franks generates a lot of cases on informant bias. They typically run something like this. The government will get a warrant based in part on the statements or claims of an informant. The affidavit won't give specific reasons to doubt that the informant is credible. Down the road, the warrant will be challenged on the ground that the affidavit failed to tell the judge of good reasons to think the informant was biased and unreliable. Maybe the informant was facing criminal charges and had every incentive to manufacture evidence that others were involved in crimes to strike a better deal for himself. Maybe the informant was the suspect's estranged spouse in the middle of a bitter divorce battle, and she was trying to get him arrested to help get custody of the kids. In each of the cases, the defendant claims that the warrant should be voided because the government failed to disclose the informant's bias. If the government hadn't misled the court, the argument runs, no warrant would have issued because the judge would have seen that the informant could not be trusted.

How has this argument fared? It depends on the case. Most of the time, though, it hasn't fared very well.

Part of the problem is that judges figure that of course informants are often biased. Informants usually have ulterior motives, and judges don't need to be told that. A helpful case is United States v. Strifler, 851 F.2d 1197, 1201 (9th Cir. 1988), in which the government obtained a warrant to search a house for a meth lab inside. Probable cause was based largely on a confidential informant who told the police that he had not only seen a meth lab in the house but had even helped others to try to manufacture meth there. The magistrate judge issued the warrant based on the informant's detailed tip. The search was successful and charges followed.

The defendants challenged the warrant on the ground that the affidavit had failed to mention the remarkable ulterior motives of the informant. The affidavit didn't mention that the "informant" was actually a married couple that had been in a quarrel with the defendants; that the couple was facing criminal charges themselves and had been "guaranteed by the prosecutor that they would not be prosecuted if they provided information"; and that they had been paid by the government for giving the information. The affidavit didn't mention any of that. A big deal, right?

According to the court, no. "It would have to be a very naive magistrate who would suppose that a confidential informant would drop in off the street with such detailed evidence and not have an ulterior motive," Judge Noonan wrote. "The magistrate would naturally have assumed that the informant was not a disinterested citizen." The fact that the magistrate wasn't told that the "informant" was guaranteed to go free and paid for the information didn't matter, as "the magistrate was given reason to think the informant knew a good deal about what was going on" inside the house.

In some cases, omitted information about a witnesses's bias is irrelevant because there is enough evidence of the crime so that probable cause was not really in question. Consider Smith v. Edwards, 175 F.3d 99 (2d Cir. 1999) (Sotomayor. J.), a horrible case involving alleged abuse of a child. A mother reported that her husband had sexually abused their daughter, and the judge issued the warrant for the husband's arrest. The husband was arrested but the charges were later dropped. The husband then sued the officer who obtained the warrant, claiming that the officer had obtained the warrant only because he had left out critical information in the affidavit. In particular, the affidavit did not inform the magistrate that the mother had instituted divorce proceedings against her husband, and it did not state that she had come to the police only after having tried unsuccessfully to obtain a restraining order to bar him from contacting her or her daughter. In the husband's telling, you needed to understand the wife's bias to know that she had made up the claims about him to get custody of their daughter.

The court held that the failure to disclose this information was irrelevant. The undisclosed information "was not material because there would have been probable cause to arrest" the husband even if the officer had included the omitted information. Even if the affidavit been "corrected" by including the omitted information, "nothing in the outcome of the Superior Court proceedings that would have negated probable cause."

Importantly, that doesn't mean that an informant's bias never needs to be disclosed. It just depends on facts of the case. It depends on how important the informant's information was to establish probable cause, and it depends on how much the alleged bias makes the information unreliable in context. If there are reasons to credit the informant despite the bias, based on the detail of the tip, the informant's history of providing reliable tips, or other information, then the background informantion about bias isn't particularly relevant. But if an affidavit hinged on an informant's claim and bias would have fatally undercut probable cause, then it has to be included in the affidavit.

United States v. Glover, 755 F.3d 811 (7th Cir. 2014), is an example of when an informant's bias has to be disclosed. In Glover, the basis for a warrant to search the defendant's home for drugs was a confidential informant who told the police that the defendant was a gang member and drug dealer who had a lot of guns in his house. The police verified that the defendant had past convictions and lived in the house, but otherwise the case for the warrant was based almost exclusively on the uncorroborated claims of the informant. In particular, the affidavit failed to say that the informant was himself a gang member with fourteen convictions who had lied to the police about his identity and been paid in the past for being an informant.

The Seventh Circuit tossed out the warrant because the affidavit didn't give sufficient reason to think the informant was reliable. The informant's tip was bare-bones and generic. It lacked the detail of someone who had special knowledge. The police hadn't corroborated the claims sufficiently. And the failure to say that the informant was a gang member was part of that, too, as knowing that fact could undercut probable cause.

In particular, the fact that the informant in Glover was himself a gang member raised the concern that the informant had simply made up claims about the defendant's drugs and guns because of gang rivalries. If the police had corroborated the tip or the informant had been reliable in the past, that could assuage concerns that the informant had just manufactured the probable cause from whole cloth. In such a case, "omission of an informant's criminal background and financial motive is not necessarily essential to the probable cause determination." But the absence of that corroboration or reason to trust the informant, and the fact that the informant's credibility was key to the case, made disclosing that informantion essential.

What do we make of these cases in the context of #ReleaseTheMemo? I think a few lessons emerge, at least assuming that the FISC judges approach omissions in affidavits in the same way judges ordinarily do in criminal cases (which seems a fair assumption to me, although I'm open to correction on that).

First, you need to know all of the facts claimed in the Carter Page FISA affidavit to know if disclosing the funding source of the Steele's research was even remotely relevant. My understanding is that FISA applications like this are rarely close calls. DOJ usually gives the FISC way more than probable cause. (At least that's my understanding: I was at DOJ and applied for warrants and a Title III order way back when, but I haven't done any FISC work.) If that's right, it means that Steele's research may have been included in the affidavit amidst a ton of other evidence. And if so, the Steele research itself may have been wholly irrelevant to the application. It's hard to see any significance to whether the funding source of irrelevant research was included. If that's right, the omission was not material, in the language of Smith v. Edwards; including it would not have negated probable cause. And you would need to assess that based on reading the entire affidavit, not just whatever is alleged in the four-page Nunes memo.

Second, even if the Steele research was a major part of the affidavit, whether the funding source would need to be disclosed depends on whether it critically altered the case for probable cause. Some of that would depend on whether the Steele research was corroborated. If the government looked into the Steele memorandum and corroborated some of its claims, it undercuts the need to disclose the funding source.

And some of that depends on identifying just what the narrative is for why the funding source was critical to establishing probable cause. I think that point is really important and too easily ignored. In #ReleaseTheMemo circles, any possible link between the Steele dossier and the Clinton campaign is like an atomic bomb. It completely annihilates any possible credibility the Steele dossier may have, leaving the exposed words of the dossier behind like the haunting shadows of the Hiroshima blast.

But that's not how actual law works. In the world of actual law, there needs to be a good reason for the judge to think, once informed of the claim of bias, that the informant was just totally making it up. As United States v. Strifler shows, that isn't necessarily the case even if the government paid the informant to talk and guaranteed that they would get out of jail if they did. Nor is it necessarily the case just because the informant is in personal feud with the suspect. What matters is whether, based on the totality of the circumstances, the information came from a credible source.

That's a problem for #ReleaseTheMemo, I think. To my knowledge, Steele was not some random person motivated by an ongoing personal feud against Trump or Carter Page. To my knowledge, he was not a drug dealer facing criminal charges who was promised freedom if he could come up with something for the government's FISA application. Instead, Steele was a former MI6 intelligence officer and Russia expert. He was hired to do opposition research because of his professional reputation, expertise and contacts. And his work was apparently taken pretty seriously by United States intelligence agencies. Of course, that doesn't mean that what's in the dossier is true. Maybe the key allegations are totally wrong. But if you're trying to argue that Steele's funding sources ruin the credibility of his research, his professional training and background make that an uphill battle.