Washington (CNN) Rick Gates' former trial attorney says the ex-Trump campaign staffer and Mueller investigation cooperator stiffed the law firm of almost $370,000.

The New York white collar defense firm Doar Rieck Kaley & Mack sued Gates on Thursday, seeking the unpaid legal fees plus interest and court costs. One of the lawyers at the firm, Walter Mack, represented Gates from the early days following his indictment in October 2017 until February of this year, days before Gates pleaded guilty. Two other lawyers also represented Gates during that time and worked closely with Mack.

In all, Mack's law firm says Gates owes them $388,525.34. He has only paid $20,000.

The new lawsuit highlights the disarray of Gates' legal representation as his fought charges against special counsel Robert Mueller. When he was first indicted, Gates split with the lawyer who had represented him while he was first under investigation. A federal public defender showed up to help him at his first court appearance following the indictment. Mack and two other defense attorneys, Annemarie McAvoy and Shanlon Wu, took him as a client days later -- and prepared to take him to trial as he maintained his innocence. Wu is a CNN legal analyst.

But in January, Gates secretly engaged another lawyer, Tom Green, to negotiate a plea deal with Mueller's office.

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