Attorneys for President Trump have repeatedly met with Special Counsel Robert Mueller and submitted memos arguing that Trump did not obstruct justice when he fired FBI Director James Comey earlier this year, The Wall Street Journal reported Thursday.

According to the Journal, the president’s legal team has also warned Mueller that Comey is an unsuitable witness. In a memo submitted in June, Trump’s lawyers described Comey as prone to exaggeration and the source of multiple leaks to the news media.

The Jounal report, which cited “people familiar with the matter,” said that Trump’s attorneys gave their memos to Mueller in an effort to close the investigation of the president for allegations of obstruction of justice.