Months after Chicago police Sgt. Donald Markham was found shot to death in the master bedroom of his Northwest Side home in what police concluded was a suicide, the FBI got a tip that the narcotics unit supervisor might have been murdered.

In the course of its investigation, the FBI — suspecting that someone killed Markham in the early-morning hours of Sept. 2, 2015 — contacted the Chicago Police Department’s Bureau of Internal Affairs. Look into Markham’s case, the FBI urged.

But police brass were concerned, sources told the Chicago Sun-Times, that the dead cop’s widow, Officer Dina Markham, who discovered the body, had worked in internal affairs, an assignment she’d held for years, until June 2016, when she was transferred to the Area North detectives division at Belmont and Western.

But Markham’s new assignment created another problem, according to sources, because she now was working in the detective division that concluded that her husband killed himself — the finding the FBI has called into question.

Newly obtained records show she was working at Area North in February when internal affairs stepped aside, handing off the case to the city of Chicago’s inspector general’s office, which began its own investigation of how the police handled her husband’s case.

The inspector general’s office continues to look into how detectives concluded Markham killed himself, according to police spokesman Anthony Guglielmi, confirming an earlier Sun-Times report. But Guglielmi wouldn’t answer questions about the case, citing that investigation.

Among the questions investigators are trying to answer: why detectives didn’t test Dina Markham for gunshot residue to determine whether she fired a gun. According to police reports, she’d had an argument with her husband earlier that night, starting at a country bar in Edison Park and continuing in their car and at home.

Dina Markham’s nine-month stint in the Area North detective division ended March 3 with her reassignment to the police department’s Bureau of Organizational Development while the FBI and the inspector general moved ahead with their investigations into her husband’s death and how the case was handled by the detective division headed by Cmdr. Kevin Duffin, records show.

The Chicago Police Department won’t say who decided to transfer Dina Markham from the Bureau of Internal Affairs to the detective unit that handled her husband’s case.

The FBI and the inspector general’s office have been investigating Donald Markham’s death at least for several months.

Dina Markham told Sun-Times reporters last month that she had been unaware authorities were looking into her husband’s death. Six days later, on May 28, she was found dead in a bathtub at her home in Old Norwood Park, the same house where her husband died.

Her death is under investigation by the Chicago Police Department and the Cook County medical examiner’s office, whose staff is awaiting toxicology reports to determine how she died. The police have said they believe she took pills and described the death as a possible suicide.

After her body was found, FBI agents showed up at the house, sources said, and so did Duffin, the Area North commander who had been Markham’s boss. Though Duffin’s detectives handled the initial investigation of Donald Markham’s death, they aren’t investigating his wife’s death, according to the police department. That case has been assigned to Area South detectives to avoid any possible conflict of interest.

Police Supt. Eddie Johnson and Cmdr. Kevin Duffin discuss the Kyrian Knox case on Tuesday at the Garfield Park lagoon.

Cmdr. Kevin Duffin, right, with Supt. Eddie Johnson at a news conference last November. | Santiago Covarrubias / Sun-Times

Duffin has declined Sun-Times requests for an interview.

Records obtained from the police department show the commander accessed Donald Markham’s case files three times over the past year. The first time was June 6, 2016, six days before Dina Markham was assigned to Duffin’s unit. The second was Nov. 8, and third time was Feb. 10, three weeks before she was transferred out of Duffin’s unit.

Donald Markham was a sergeant in the department’s narcotics bureau. His supervisor, Lt. Michael Ryle, was called to the scene after Markham was found dead because he was Markham’s boss, though he wasn’t involved in the investigation.

He was one of 19 cops who showed up at the Markham home, according to police reports.

Ryle has spoken with the FBI, sources said. He told a reporter to direct any questions to the FBI or the police.

Neither the FBI nor the city inspector general’s office would comment.

Also, Cook County Inspector General Patrick Blanchard says his staff has now begun a “review” of the medical examiner’s handling of Donald Markham’s death, which a county pathologist ruled was a suicide.

Markham’s body was removed by police from the home before a medical examiner’s investigator could view the shooting scene.

According to city records, the police notified the medical examiner’s office within an hour after Dina Markham called 911. But the medical examiner’s office has said the police didn’t alert them until about two and a half hours after her 911 call — when the body was already on the way to the morgue.

READ MORE: Chicago cop couple’s mysterious deaths under investigation, May 31, 2017

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