A federal prosecutor faces an allegation that he’s interfering with a former death row inmate’s pursuit of civil rights claims against three police detectives.

In a letter sent to the U.S attorney Tuesday, sole practitioner H. Candace Gorman contends Assistant U.S. Attorney William R. Hogan Jr. is abusing his position by playing a personal role in Nathson Fields’ federal lawsuit.

Fields alleges three Chicago detectives framed him for the murders of two gang members.

Gorman faxed the letter to Chicago’s top federal prosecutor, U.S. Attorney Zachary T. Fardon, and Inspector General Michael E. Horowitz with the U.S. Justice Department in Washington, D.C.

In proceedings in the lawsuit last year, Gorman alleges in the letter, Hogan arranged for the federal prisoners who testified in favor of the detectives to be brought to court even though he himself also was a defense witness.

Hogan has continued to wait outside the courtroom during proceedings in the suit and to talk with the detectives and their defense lawyers, Gorman alleges.

She alleges Hogan had a private conversation Monday with one of those lawyers, Shelly B. Kulwin of Kulwin, Masciopinto & Kulwin LLP, following a hearing in the suit.

The two men went to a witness room in the Dirksen Federal Courthouse, Gorman alleges, after Hogan saw Kulwin exit the courtroom, pointed to the room and yelled “in there.”

Gorman wrote that Kulwin represented Hogan in the 1990s in his successful battle to regain his job after he was fired amid controversy over his handling of the El Rukn street gang prosecutions.

Gorman also wrote that Fields’ original co-defendant — Earl Hawkins, an El Rukn member and convicted murderer — was released from prison in December shortly after testifying against Fields in the suit. The release came 12 years early, she alleges.

Hogan acted as Hawkins’ “personal representative” in his parole hearing, Gorman alleges, and arranged for two of the detectives sued by Fields to send letters of support to the hearing examiner who recommended Hawkins’ release.

“I ask that you conduct your own investigation into AUSA Hogan’s role in the Fields civil rights case — or at the very least that you rein him in and keep him away from this case and the courtroom when the case is up,” Gorman wrote.

Spokeswoman Kimberly Nerheim of the U.S. attorney’s office declined to comment. Neither Hogan nor the Justice Department could be reached for comment.

In a filing in the suit in January, the U.S. Parole Commission described assertions that there was a secret deal to release Hawkins early in exchange for his testimony as “wild allegations.”

In a sworn declaration accompanying the filing, Hogan contends a plea agreement reached in 1989 as well as an independent determination by the hearing examiner led to Hawkins’ release.

The parole commission had not seen the letters from him or the detectives, Hogan contends, when it granted Hawkins parole.

In both the declaration and an affidavit filed in February, Hogan says he had not had contact with the parole commission beyond a letter describing Hawkins’ cooperation as required by the plea agreement.

Today, Kulwin contended Gorman’s description of Monday’s incident “is wrong.”

“Further, nothing directs or influences my representation of a client other than their best interests and the rules governing our profession,” he said. “This case is and will be no different.”

In 1986, Fields and Hawkins were convicted in a bench trial before then-Cook County Circuit Judge Thomas J. Maloney of murdering two men. They were sentenced to death.

In 1993, Maloney became the first judge in Illinois history to be convicted of fixing murder cases.

Fields sought a new trial, alleging Maloney accepted a $10,000 bribe to acquit him and Hawkins but then returned the money and convicted the pair after becoming suspicious that the FBI was investigating him.

Fields won a new trial. Hawkins agreed to testify against him in return for a reduced sentence on lesser charges.

Fields was acquitted in 2009. He had spent 18 years in prison, 12 of them on death row.

Following his acquittal, Fields obtained a certificate of innocence under Illinois law. Hawkins testified against Fields in that proceeding.

In his civil rights suit, Fields alleges the detectives — David O’Callaghan, Joseph Murphy and Daniel Brannigan — faked evidence, withheld exculpatory materials and coerced witnesses to make false identifications.

Last year, a jury in U.S. District Judge Matthew F. Kennelly’s court found in favor of Fields on his due process claim against O’Callaghan and awarded him $80,000.

The jury found in favor of the defendants on all other claims.

This month, Kennelly concluded that errors he himself made during the proceedings entitled Fields to a new trial.

Kennelly ordered a new trial on damages only on Fields’ due process claim against O’Callaghan. He also granted a new trial to determine both liability and damages on all the other claims.

The trial is set for Nov. 30.

The case is Nathson E. Fields v. City of Chicago, et al., No. 10 C 1168.

Gorman said the case has taken an emotional toll on Fields.

“It’s been difficult for him,” she said. “He’s a very upbeat kind of person, but this has been hard on him.”