Former FBI agent Peter Strzok helped write the controversial letter to Congress sent by then-FBI Director James ComeyJames Brien ComeyInspector general testifies on FBI failures: Five takeaways Horowitz offers troubling picture of FBI's Trump campaign probe GOP senator to FBI: 'Someone's got to be fired' MORE announcing the reopening of the probe into Democratic presidential nominee Hillary ClintonHillary Diane Rodham ClintonDemocrats seek leverage for trial Davis: Trump vs. Clinton impeachments – the major differences Sharice Davids to vote for Trump impeachment articles: 'The facts are uncontested' MORE, according to emails obtained by CNN. 

Strzok, who in 2016 sent dozens of anti-Trump text messages in what conservatives have called clear evidence of bias, co-wrote the first draft of the letter but was unsure about reopening the investigation so close to the election, sources told CNN in a report published Wednesday. 

The day after Strzok sent his draft to colleagues, Comey released the final version of the letter, bringing Clinton's emails back into the spotlight just weeks before Election Day.


Comey reopened the investigation that October, when thousands of emails of Clinton's surfaced on the laptop of former aide Huma Abedin's husband Anthony Weiner in a separate investigation. 

Clinton and top Democrats have said the letter was a key factor in her election loss to President TrumpDonald John TrumpThe Hill's Morning Report - Sponsored by AdvaMed - House panel expected to approve impeachment articles Thursday Democrats worried by Jeremy Corbyn's UK rise amid anti-Semitism Warren, Buttigieg duke it out in sprint to 2020 MORE.

Comey has said that it made him "mildly nauseous" to think that reopening the Clinton probe may have swayed the election, but that he would have made the same decision again.

Strzok later went on to work on the Justice Department's probe into possible collusion between the Trump campaign and Russia, but was removed by special counsel Robert MuellerRobert (Bob) Swan MuellerTrump says he'll release financial records before election, knocks Dems' efforts House impeachment hearings: The witch hunt continues Speier says impeachment inquiry shows 'very strong case of bribery' by Trump MORE after the politically charged texts he exchanged with an FBI lawyer were revealed.

Trump and congressional Republicans say the texts are evidence that the probe into the Trump campaign is biased, while Democrats say they are trying to undercut Mueller's credibility. 

Trump accused Strzok of "treason" in a Wall Street Journal interview earlier this month.

Strzok also reportedly edited a key line in Comey's statement in July 2016 originally announcing Clinton would face no charges over her "home brew" server. He changed the phrase "grossly negligent" to "extremely careless" in regards to her actions.