The lawyers last year tried to persuade Mr. Mueller to investigate Mr. Comey, his former colleague, to no avail.
The Trump-Comey war took on new dimensions last week as Mr. Mueller won a guilty plea from former Trump attorney Michael Cohen, who admitted to lying to the Senate Select Committee on Intelligence about a proposed election-year Trump Organization Moscow hotel deal.
“The Cohen plea of lying to Congress by the special counsel raises the very serious question as to why the special counsel has refused to investigate and prosecute the false statements and testimony of James Comey, the main accuser of the president, before the Senate Judiciary and intel committees,” former Trump attorney John Dowd told The Washington Times.
Mr. Dowd and his colleagues filed a complaint with the Justice Department and Mr. Mueller last year. It says, in part, that Mr. Comey was dishonest in May 2017 when he said he never took steps for FBI surrogates to leak stories about Mr. Trump to the news media.