Grassley and Graham, both members of the Senate Judiciary Committtee, have accused Steele of making false statements to the US government about the "distribution" of the document's claims.
"Everyone needs to follow the law and be truthful in their interactions with the FBI," Grassley is quoted as saying in the letter. "If the same actions have different outcomes, and those differences seem to correspond to partisan political interests, then the public will naturally suspect that law enforcement decisions are not on the up-and-up."
Most of the allegations levied against Steele were classified, as they were based on secret meetings between him and the FBI that have since been passed on to the Judiciary Committee.
Steele, a former MI-6 agent, was hired by opposition research firm Fusion GPS to investigate alleged ties between then-presidential candidate Donald Trump and his campaign team with Russian actors. Fusion was paid for the investigation by Perkins Coie, an intermediary for the Democratic National Committee and the Hillary Clinton presidential campaign.
The dossier was unveiled to the public in early 2017. Almost a year after its publication, the vast majority of the salacious claims contained within remain unverified. The dossier forms much of the basis for Congress and the DOJ's investigation into aforementioned alleged ties between Trump and Russia. The FBI also intended to pay Steele to continue the research he had done for Fusion GPS until the dossier was revealed to the public by BuzzFeed News in January 2017.
Fusion GPS' lawyer Joshua Levy has referred to the scrutiny on Steele as a "smear" meant to muddy the waters of the investigation. "Publicizing a criminal referral based on classified information raises serious questions about whether this letter is nothing more than another attempt to discredit government sources, in the midst of an ongoing criminal investigation," Levy said in a statement. "We should all be skeptical in the extreme."
The DOJ, which appointed special counsel Robert Mueller to investigate alleged ties between Trump and Russia in May 2017, is not obligated to follow Grassley and Graham's recommendation. They had no immediate comment on the request.
While the initial investigation was bipartisan in nature, it has increasingly fractured across party lines. This is the first criminal referral in the Russia Gate investigation to come from the GOP. However, House Intelligence Committee Chair Rep. Devin Nunes (R-CA), has subpoenaed Fusion GPS' bank records to investigate their role in the authoring of the dossier.