The Colorado Supreme Court Attorney Regulation Counsel acknowledged the investigation Saturday in a letter to the person who filed the complaint, Sean Harrington.
"I write to inform you that the Office of Attorney Regulation Counsel has re-opened the above-referenced request for investigation," wrote Louise Culberson-Smith, assistant regulation counsel in a letter dated Oct. 23.
During its investigation, the counsel will determine if there is reasonable cause to believe Nottingham engaged in misconduct, which would then prompt a disciplinary hearing into his law license.
Depending on the outcome of that hearing, Nottingham could be disbarred and lose his license to practice law.
Harrington's initial request for Nottingham to be investigated for moral turpitude on April 1 was denied by the counsel, pending an investigation by the 10th Circuit Court of Appeals.
"The only reason it's doing its investigation now is because it's become a sensational, salacious scandal," said Harrington.
Nottingham announced his resignation earlier this month and he will officially step down from the bench on Wednesday in response to the multiple investigations into his possible misconduct.
While Harrington is pleased the counsel is finally investigating his complaint against Nottingham, he thinks it should have started it in April at the time of his first request.
"I would be pleased if they conducted any and every investigation pursuant to the disciplinary rules; usually they don't," said Harrington.
The counsel refused to comment about the new investigation, saying the process is confidential.
Nottingham and his attorney, Stephen Peters, have not returned any calls from 9NEWS for comment in the last two weeks.
In August 2007, Nottingham's ex-wife Marcie Jaeger told 9Wants to Know she found credit cards charges from a strip club in downtown Denver that totaled more than $3,000 in two days.
When questioned about those charges in his Eagle County District divorce case, Nottingham testified he was "...ashamed and mortified just telling you that is the Diamond Cabaret, a topless establishment."
When attorneys asked him how he could have spent so much money there in two nights, he said he couldn't recall, explaining, "I had a lot to drink... and I don't remember."
In September 2007, Jeanne Elliot told 9Wants to Know that Nottingham parked in a handicapped parking space. After she blocked his vehicle in the space with her wheelchair, Elliot said Nottingham put his car in reverse.
"I could tell from his back-up lights going on and I thought, 'Oh boy! He's going to back over me," Elliott told 9NEWS in October 2007.
Elliott also claims that Nottingham told her, "If you don't get out of my way, I'm a federal judge and I'm going to call the U.S. Marshals and have them arrest you."
In a written statement, Nottingham said he regrets parking in the space, "But respectfully disagrees with the remainder of Ms. Elliott's version of this incident."
Nottingham received a ticket for parking in the handicapped parking space and paid the $100 fine.
In March 2008, 9Wants to Know reported that Nottingham's full name and personal cell phone number appeared on a list of clients for the prostitution business, Denver Players.
Denver Police and IRS agents shut down the business after they served search warrants on the businesses in February 2008. A grand jury has been interviewing witnesses related to the prostitution businesses, 9NEWS learned.
On Oct. 16, two former prostitutes told 9Wants to Know that Nottingham was a client of another escort agency called Bada Bing of Denver in 2003 and 2004.
One of the women claims Nottingham drove her to his home in the Hilltop area in March. She says he made them both undress to make sure they weren't wearing wire. Then she says he told her to make up stories and lie to federal investigators about the true nature of their relationship. The woman did lie to an investigator and later filed a complaint with the 10th Circuit Court of Appeals.
Nottingham announced his resignation on Oct. 21, days after learning about the newest allegations from the two former prostitutes.
A statement released to some Denver media said Nottingham resigned his commission as a United States district judge for the District of Colorado because "...it is in the best interest of all concerned. It is in the public interest and the interest of the federal judiciary because it will terminate his judgeship and being to restore public confidence in an institution which he profoundly respects."
The statement also said that Nottingham is "deeply remorseful for his actions" and "embarrassed and ashamed."
The FBI is investigating the allegations that Nottingham told the former prostitute to lie to investigators.
If you have any story tips, please e-mail Deborah.Sherman@9NEWS.com.
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