President Trump's legal team has been busy over the past few months making a case to special counsel Robert Mueller that Trump did not obstruct justice when he fired FBI Director James Comey, according to a report Thursday.

The attorneys have met with Mueller multiple times and have submitted memos defending Trump, who fired Comey in May.

Among the memos submitted, the Wall Street Journal reports that one sent to Mueller outlines the president's constitutional authority to determine who fills the position of FBI director.

Another one submitted in June noted why Comey was an unreliable director and witness, describing him as unreliable during his congressional testimony and calling him a source of leaks to media outlets.

During his June testimony, Comey admitted that he turned over memos detailing his meetings with the president to special counsel Mueller, signaling that Mueller may turn towards Trump during his investigation.

The former FBI director also revealed that he was the source that leaked contents of those memos to media outlets.

The memos and meetings now being had between Mueller and Trump's legal team signify the beginning of Trump's attorney's defense of the president to special counsel Mueller after it was reported in June by the Washington Post that Mueller's Russia probe would be investigating Trump for possible obstruction of justice. That would go beyond the probe's initial look into Russian interference in the 2016 election and possible collusion between the Trump campaign and Russia.

Alongside the federal probe are a number of congressional panels also looking into Russian interference.

Deputy Attorney General Rod Rosenstein appointed Mueller to head the federal investigation back in May. Rosenstein did so after Attorney General Jeff Sessions recused himself.

When asked for comment, the White House referred the Journal to Trump's special counsel, Ty Cobb.

"We have great respect for the special counsel. Out of respect for his process we will not be discussing incremental responses," Cobb said.