Four of the co-defendants in former President Donald Trump's criminal racketeering case in Georgia are demanding an investigation into Fulton County District Attorney Fani Willis's office, citing a legal services brochure for one or her allies' law firm, reported The Atlanta Journal-Constitution on Friday.

"In a Thursday court filing, attorneys representing David Shafer asked a Fulton judge to hold an evidentiary hearing about a brochure the former Georgia GOP chairman received from [special prosecutor] Nathan Wade’s law office. On Friday, three additional defendants joined Shafer’s motion after receiving similar mailers: Sidney Powell, Cathy Latham and Jeffrey Clark," reported Tamar Hallerman. "The filing from Shafer’s team came in response to an unsolicited brochure that Wade’s two-person law firm, Wade & Campbell, sent to Shafer’s home address weeks after the Republican was indicted on eight charges, including racketeering and impersonating a public officer."

The brochure in question "includes a smiling photo of Wade and his law partner, Christopher Campbell," noted the report. "At the bottom is Shafer’s name and one of the charges filed against him. Attached was a letter signed by Campbell advertising the firm’s legal services."

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Shafer's attorneys argue that this constitutes improper contact by the prosecutors' office and a conflict of interest.

One legal expert said that it was unlikely a violation of ethics but still a "bad look." Another, NYU Law professor emeritus Stephen Gillers, said, “The prohibition of contact with a represented party requires more than the receipt of a brochure. I suspect that the brochure might have been sent routinely because firms do solicit business this way from newly indicted persons without any firm lawyer participating in the decision.”

Shafer is one of the purported false electors accused as part of the plot to throw out the real ones in the state of Georgia, a scheme that took place in seven states and is also being prosecuted in Michigan. Some attorneys close to Trump who helped craft the scheme, including John Eastman, have been charged in Georgia as well.