The search warrant, obtained by 9Wants to Know, was served to Microsoft Corporation in Mountain View, California on March 4.
The IRS alleges Brenda Stewart ran Denver Players or Denver Sugar and Stewart has connections to the two e-mail addresses that were searched.
9Wants to Know has reported Federal Judge Edward Nottingham had ties to the escort service which catered to prominent clients including judges, lawyers, businessmen, athletes and politicians.
The warrant, which federal court records show was returned March 13, allowed the IRS to seize contents of the e-mail accounts firstname.lastname@example.org and email@example.com.
Investigators believe the addresses were used for prostitution in connection with the escort service.
The search warrant gave investigators permission to seize sent, received and draft email messages as well as the contents of the trash folders.
Investigators received 3,101 files which include e-mails, photos, spreadsheets, graphics, and Internet files.
Investigators have not announced what's included in the files but in the application and affidavit for search warrant, IRS Special Agent Chad Eichelberger said he believes the e-mail accounts "…will contain evidence of violations…" of federal prostitution and tax law.
The escort business was shut down in January after the IRS and Denver Police investigators served search warrants at her home and a brothel on Fillmore Street.
A nearly two-year joint investigation into the prostitution service by the IRS and the Denver Police led to the execution of the search warrant at Stewart's home on Jan. 25. Stewart has not been arrested or charged for any crime involved in the case.
During the January search, court documents show investigators confiscated computers, financial records, client books, credit card receipts and other items from Stewart's home at 1305 Monaco Parkway in Denver. Some employees also kept copies of some of the transactions.
9Wants to Know has learned the U.S. Court of Appeals for the 10th Circuit is investigating Nottingham for improper judicial conduct after his full name and personal cell phone number appeared on a list of clients from a Denver prostitution business.
Nottingham ascended to chief judge in 2007 and presided over the insider trading trial of former Qwest CEO Joe Nacchio. Earlier this week, a three-judge panel with the 10th Circuit Court of Appeals ordered a new trial for Nacchio because Nottingham did not allow an expert witness for the defense to testify.
Victoria Parks, the deputy circuit executive at the U.S. Court of Appeals would not confirm an investigation into Judge Nottingham by the 10th Circuit Court of Appeals
U.S. Attorney Troy Eid also had no comment about any investigation and neither did the Denver Police Department.
Judge Nottingham has not responded to numerous attempts for comment on this story.
This is the third investigation by the 10th Circuit Court of Appeals into Judge Nottingham's conduct in the past year.
The first began last August when 9Wants to Know obtained court records into the judge's behavior at Denver strip clubs.
9NEWS reported that Nottingham testified during his divorce he had spent more than $3,000 at a Denver strip club in just two days and that he was "too drunk to remember" how he'd spent the money.
Divorce proceedings started shortly after Nottingham's ex-wife Marci Jaeger discovered questionable charges on his credit card bills.
The 10th Circuit Court of Appeals also has an open investigation into a ticket Judge Nottingham received for illegally parking in a handicapped parking spot last fall.
The judge was ticketed by Denver Police after a disabled woman discovered his vehicle did not have the proper handicapped parking placard or license plate.
Judge Nottingham was appointed to the federal bench in 1989 by President George H. W. Bush. It is a lifetime appointment.
When Judge Nottingham presided over the insider-trading trial of Qwest CEO Joe Nacchio last summer, he lectured Nacchio about morality.
"If it is perceived that there is one law for the rich and one law for everyone else, the law ultimately falls into disrespect," said Judge Nottingham to Nacchio. "The law does not care about your station in life."
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