- James Comey implied allegations contained in a dossier could be subject to a federal probe
- President Donald Trump and his supporters have dismissed the document
Lawyers for Fusion GPS, a political research firm run by a former Wall Street Journal reporter, wrote to Grassley in April that they could not provide backup documents behind the dossier -- written by former British intelligence agent Christopher Steele
-- because of client confidentiality agreements.
But Grassley responded this week he may force the firm to produce the records.
"While any confidentiality agreements may prevent Fusion GPS from complying voluntarily, they do not supersede the committee's constitutional authority to compel the production of information," Grassley, an Iowa Republican, said in a letter written Wednesday and released publicly Friday.
President Donald Trump and his supporters have dismissed the document -- with some fairly stunning allegations about Trump and his campaign -- as being "dodgy" and faulty.
And former FBI Director James Comey acknowledged privately to Trump that the one dossier item about Trump being filmed in Russia with hookers was particularly "salacious," according to Comey's testimony before the Senate intelligence committee this week.
But Comey also implied that other allegations contained in the document could be the subject of the federal probe.
"If the FBI receives a credible allegation that there is some effort to co-opt, coerce, direct, employ covertly an American on behalf of the foreign power, that's the basis on which a counterintelligence investigation is opened," Comey told committee Chairman Richard Burr.
Asked by Burr if he could comment on the fact that the document was "100% directed" at Trump, Comey said it was not something he could discuss in public.