Here are the times Republicans tried to undermine the Russia investigation

Those attacks have also led Trump and some in the GOP to attack the FBI and Department of Justice.

Here's a look at all the times Republican lawmakers tried to undermine the Russia investigation.

Devin Nunes recused himself, but kept investigating anyway

House Intelligence Chairman Devin Nunes continued to be a powerful force in the House's Russia investigation, despite his promise that he stepped aside as the head of the probe as he came under scrutiny himself from the House Ethics Committee.

In December, the Ethics Committee cleared Nunes in its investigation into whether he had disclosed classified information to the Trump White House, creating an avenue for the California Republican to return to the helm of the panel's Russia investigation.

Nunes' return further inflamed the partisan fervor surrounding the investigation into Russian meddling in the 2016 US election.

Which leads to his memo.

Nunes' FISA memo

Nunes wrote a memo on the House Russia investigation that quickly became a conservative rallying cry, with Republicans on Capitol Hill demanding that the documents be released.

The memo is a four-page summary of his investigation into the FBI and Justice Department's use of the Foreign Intelligence Surveillance Act. It details allegations of FBI missteps during the 2016 election.

House conservatives who have reviewed the report said the public would be shocked to learn about what they believe is widespread abuse by the FBI.

Democrats, like Rep. Adam Schiff of California, the top Democrat on the House Intelligence Committee, argued that the pressure campaign is nothing more than a partisan attempt to protect Trump. Schiff called the memo a "profoundly misleading set of talking points drafted by Republican staff attacking the FBI and its handling of the investigation."

Assistant Attorney General Stephen Boyd sent a letter to Nunes saying it "would be extraordinarily reckless" for the House Intelligence Committee to release a classified memo publicly "without giving the Department and the FBI the opportunity to review the memorandum." Boyd's letter said the Justice Department is "currently unaware of any wrongdoing relating to the FISA process," but that the department takes any allegation of such abuse seriously and "we agree that any abuse of that system cannot be tolerated."

The push to publicly release the Nunes report added another layer to the political fight between Democrats and Republicans in Congress over the FBI and Mueller's investigation into possible collusion between Russian officials and the Trump team, which is playing out in investigations being conducted by the Intelligence, Judiciary and Oversight committees.

Trump tried to fire Mueller in June

Though he's since called the report "fake news," a source told CNN that Trump had called for the firing of Mueller last June. White House counsel Don McGahn refused to order the Justice Department to fire Mueller because he disagreed with the President's reasoning, the source said. However, according to the source, McGahn did not threaten to resign directly to the President.

The New York Times was first to report that Trump called for Mueller's ouster in June 2017.

"Fake news, folks. Fake news," Trump said when questioned about the revelation as he entered the World Economic Forum in Davos.

"Typical New York Times," he added.

The timing last summer was about a month after Trump fired former FBI Director James Comey in May. Later that month, Mueller was appointed by the Department of Justice to manage the special counsel investigation into possible Russian meddling in the 2016 election.

Criticism following misplaced texts between Strzok and Page

A trove of missing text messages exchanged between FBI employees who shared an anti-Trump bias gave fuel to criticism of the bureau.

The messages between Peter Strzok and Lisa Page are of particular interest to Republicans who have pushed the idea that there is an anti-Trump bias at the FBI.

Strzok, who was romantically involved with Page, was a member of the FBI team investigating Hillary Clinton's email server and, later, a member of Mueller's special counsel operation.

The gap in the exchange between the FBI officials was revealed to lawmakers by the Justice Department as it produced a second batch of the pair's text messages to six congressional committees last weekend. The texts themselves were first discovered as part of an internal investigation by the inspector general into the FBI's handling of the Clinton email investigation.

Trump called the matter "one of the biggest stories in a long time," and Attorney General Jeff Sessions has promised to "leave no stone unturned" in an investigation to determine how the messages, sent on bureau-issued phones, were not collected by the FBI's retention software.

The Justice Department's inspector general informed lawmakers Thursday that the messages were eventually discovered, blaming technical issues with the FBI's retention software.