Did the FBI commit crimes by using the infamous Steele dossier about President Trump as grounds for FISA warrants to spy on Trump campaign aide Carter Page? This is the issue raised yesterday by House Intelligence Committee chief Rep. Devin Nunes’ letter to Attorney General Jeff Sessions.

The dossier contains claims that were assembled by Christopher Steele, a former British spy and FBI informant, using Russian sources for Fusion GPS, an opposition research firm, that was paid by the DNC and the Hillary Clinton campaign. Former FBI Director James Comey has characterized those claims as “salacious” and “unverified”. Nevertheless, the dossier was the basis for the FBI’s investigation of Trump’s campaign and, to all appearances, the basis for special counsel Robert Mueller’s investigation of collusion between the Trump campaign and Russia.

In his letter, Nunes states that, in using the dossier as the basis for a FISA warrant, the FBI violated “basic operating guidance” set forth in its Domestic Investigations and Operations Guide. Moreover, according to Nunes, the FBI may have violated criminal statutes by using unverified information during the 2016 election to obtain a surveillance warrant on Page.

A 2011 version of the FBI operations guide states that the “accuracy of information contained within FISA applications is of utmost importance… Only documented and verified information may be used to support FBI applications to the court.”

But, according to Nunes, the dossier was unverified contrary to the FBI manual which provides that information in a FISA application must be thoroughly vetted and confirmed.

Nunes listed five criminal statutes that may have been violated, including contempt of court, obstruction of justice, conspiracy and willfully depriving a person of a right protected by the Constitution.

“Former and current DOJ and FBI leadership have confirmed to the committee that unverified information from the Steele dossier comprised an essential part of the FISA applications related to Carter Page,” Nunes wrote.

Nunes’ letter seeks an answer from Sessions whether those protocols, that demand verified information only, have been changed. And if not, what is the DOJ doing to hold those who violated the requirements responsible.

Nunes’ letter raises nothing new regarding FISA procedures. There has never been any question that the FBI and DOJ must base probable cause for FISA warrants on reliable verified information.

The real news here is that Nunes publicly sent the letter to the Attorney General raising these fundamental issues. It looks like a shot across Sessions’ bow by the Republican majority on the House Intelligence Committee which has already called for a special counsel to investigate Comey’s FBI and Obama’s DOJ. This follows on the heels of this tweet by the President:

“Why is is A.G. Jeff Sessions asking the Inspector General to investigate potentially massive FISA abuse. Will take forever, has no prosecutorial power and already late with reports on Comey etc. Isn’t the I.G. an Obama guy? Why not use Justice Department lawyers? DISGRACEFUL!”

Nunes’ letter looks like an endorsement of the president’s position. The pressure is mounting. Will Sessions appoint a special counsel? Or will he resign?

Stay tuned.