It was based on information from initially anonymous sources known to the author, counterintelligence specialist Christopher Steele. Steele, a former head of the Russia Desk for British intelligence (MI6), was writing the report for the private investigative firm Fusion GPS, that was paid by Hillary Clinton's campaign and the Democratic National Committee (DNC). The dossier's 17 reports allege that Trump campaign members and Russian operatives had conspired to cooperate in Russia's election interference to benefit Trump. It also alleges that Russia sought to damage Hillary Clinton's candidacy. It was published by BuzzFeed News on January 10, 2017, without Steele's permission. Their decision to publish the reports without verifying the allegations was criticized by journalists. However, a judge defended BuzzFeed's action as the public has a right to know so it can "exercise effective oversight of the government".
The United States intelligence community and most experts have treated the dossier with caution due to its unverified allegations. While compiling the dossier, Steele passed his findings to both British and American intelligence services. The U.S. intelligence community took the allegations seriously, and the Federal Bureau of Investigation (FBI) investigated every line of the dossier and identified and spoke with at least two of Steele's sources. The Mueller Report contained passing references to some of the dossier's allegations but little mention of its more sensational claims.
While Steele's documents played a significant role in initially highlighting the general friendliness between Trump and the Putin administration, the veracity of specific allegations is highly variable. Some have been publicly confirmed, others are plausible but not specifically confirmed, and some are dubious in retrospect but not strictly disproven. While the dossier played a central and essential role in the seeking of FISA warrants on Carter Page, it did not play any role in the intelligence community's assessment about Russian actions in the 2016 election, and it was not the trigger for the opening of the Russia investigation into whether the Trump campaign was coordinating with the Russian government's interference in the 2016 presidential election. The dossier is a factor in several conspiracy theories promoted by Trump and his supporters
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