VIDEO: Previous coverage on this issue

Caren Morrison, a Georgia State University law professor and former federal prosecutor in New York, said Reed would be wise to retain representation whether he faces any legal peril or not.

“Let’s remember, Kasim Reed is a lawyer, so he’s smart and he’s going to get the best legal counsel he can get,” Morrison told Channel 2. “That’s exactly what I would do.”

Phone and text messages left Thursday with Reed were not immediately returned. A spokesman for Reed said the former mayor had no comment. Gillen did not respond to a text or email.

The two people who identified Gillen declined to be named because of the sensitivity of the federal investigation.

Elvin “E.R.” Mitchell Jr., right, stands with his attorney, Craig Gillen, after Mitchell was sentenced in October 2017 to five years in prison as part of the federal investigation of Atlanta City Hall. HYOSUB SHIN / HSHIN@AJC.COM

The federal investigation of City Hall, which dates to at least 2015, has so far netted guilty pleas from two senior Reed aides — former chief purchasing officer Adam Smith and former deputy chief of staff Katrina Taylor-Parks. Both admitted to accepting bribes.

Two construction company CEOs also have admitted to conspiring to pay bribes to win lucrative city contracts.

Gillen is a veteran criminal defense attorney and a former federal prosecutor who served as an assistant U.S. Attorney in the Northern District of Georgia, which is overseeing the probe of City Hall.

As an assistant U.S. Attorney, Gillen successfully prosecuted former U.S. Rep. Patrick Swindall, and he also was deputy independent counsel during the Iran/Contra saga.

After leaving the federal government, Gillen was part of former Atlanta mayor Bill Campbell’s defense team.

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Gillen is no stranger to the government's current corruption investigation. He previously represented one of the two CEOs, Elvin "E.R" Mitchell Jr., the first person charged and to plead guilty in the investigation. Mitchell was sentenced to five years in federal prison for conspiring to pay more than $1 million in bribes to win city contracts.

Mitchell agreed to cooperate with the government as part of his plea deal.

A third former senior city official, Mitzi Bickers, was indicted last year on charges she accepted more than $2 million in payments from Mitchell and contractor Charles P. Richards Jr. in exchange for her help in winning city business. Bickers has pleaded not guilty.

Morrison told Channel 2 Gillen’s defense of Mitchell and potential appointment to represent Reed suggests Mitchell hasn’t or isn’t expected to provide information related to Reed.

Lawyers who spoke to the AJC about the matter said Gillen, having represented another party in the federal investigation, would likely need to obtain a waiver from Mitchell and Reed to ensure that any potential conflict is resolved to the satisfaction of both parties and the court.

Our reporting

The AJC and Channel 2 Action News investigated credit card spending by former Atlanta Mayor Kasim Reed and members of his cabinet and security detail. A federal grand jury followed those reports by issuing subpoenas related to Reed and spending by the former mayor and members of his staff. The AJC and Channel 2 remain the most authoritative sources for developments in the federal investigation.