On a hot summer night in 2015, Chicago Police Sgt. Donald Markham’s wife found him dead in their bed with a bullet wound to his head hours after they’d argued at a bar and later at their home, according to police reports.

But before a Cook County medical examiner’s investigator could view the scene — standard procedure — police removed the body of the 51-year-old narcotics cop from the home in the upscale Old Norwood Park neighborhood on the city’s Far Northwest Side, records show.

That’s among several details that have emerged as the FBI and the city of Chicago’s inspector general have launched investigations into how the Chicago Police Department handled the case, which the police determined was a suicide. Investigators want to know whether someone killed Markham and the police mishandled the investigation or were involved in a cover-up, according to sources and records obtained by the Chicago Sun-Times.

Now, the case has taken a shocking turn. Markham’s widow, Dina Whitson Markham, 47, also a veteran Chicago cop, was found dead Sunday in the bathtub of the house where her husband died nearly two years earlier. Authorities say she appears to have taken her own life, having taken pills, though toxicology test results haven’t been completed, and the police investigation is ongoing.

Days earlier, Dina Markham had told the Sun-Times she didn’t know her husband’s death was under renewed investigation.

The FBI and inspector general’s investigations into how the police handled Donald Markham’s death have been ongoing for several months, according to records and sources who spoke on condition of anonymity. It’s unclear what sparked the investigations. Neither agency would comment.

Investigators have sought records about his death from the medical examiner’s office, according to a Feb. 21 subpoena obtained by the newspaper.

The assistant medical examiner who conducted the autopsy on Donald Markham “is aware the case is being investigated but has no details about the nature of the investigation,” a Cook County spokeswoman said.

Suspicious deaths reported to the police, including possible suicides, are supposed to be “immediately” reported to the medical examiner, under county ordinance. “Upon receipt of a report,” the medical examiner “shall go to the location of the body and take charge of same, and shall begin his/her investigation with an examination of the scene.”

With suspected suicides or homicides, the bodies are not supposed to be “handled, disturbed . . . or removed from the place of death by any person except with the permission of the medical examiner” except under limited instances.

Records from the city Office of Emergency Management and Communications show the medical examiner’s office was notified within an hour, by 3:56 a.m. But the medical examiner’s office says it wasn’t notified until about an hour and a half later, at 5:27 a.m.

Besides allowing Donald Markham’s body to be removed, along with pillows and sheets, before a medical examiner’s investigator could examine the scene, sources say investigators’ other concerns include the failure to test Dina Markham for gunshot residue to determine whether she fired a weapon during the early-morning hours of Sept. 2, 2015, when her husband died.

The Chicago Police Department gives “primary detectives” discretion to request a gunshot residue test — which, though not foolproof, can indicate whether someone fired a weapon or didn’t.

Donald Markham’s .380-caliber, semi-automatic Glock handgun was in his right hand, the police reports say. The Illinois State Police crime lab found that “Donald Markham discharged a firearm, contacted a [gunshot residue]-related item, or had both hands in the environment of a discharged firearm.” Toxicology reports found his blood-alcohol level was well above the .08 percent standard for drunk driving.

There’s no indication in police records that officers canvassed the Markhams’ neighbors to see if anyone heard the gunshot. There’s also no indication police interviewed patrons and workers at an Edison Park bar where the police say the Markhams argued earlier that night.

Statements from the Markhams’ children — three who were home at the time, according to police — about the night their father died were blacked out in the police reports the Sun-Times obtained.

Donald Markham, who lost the 2007 election for 41st Ward alderman, did not leave a suicide note and hadn’t previously tried to kill himself or threatened to do so, according to the medical examiner’s report.

Former police Lt. Denis P. Walsh. | Sun-Times files

The investigation of his death was supervised by Area North Lt. Denis P. Walsh. Three months later, in December 2015, then-Interim Supt. John Escalante took steps to fire Walsh over his role in the botched investigation into the killing of David Koschman, who died after he was punched by a nephew of former Mayor Richard M. Daley.

Walsh, who had admitted keeping missing Koschman files at his home, had been accused of “making a false report,” “inattention to duty” and “incompetency or inefficiency” in the Koschman case. Walsh resigned in February 2016, ending the effort to fire him.

Walsh declined to comment.

The Markhams had been quarreling the night he died, according to police reports prepared by Detective Brian Spain and approved by Walsh. Donald Markham was upset that his wife had kept him out late drinking at the Firewater Saloon in Edison Park when he had to report for duty in the morning, a Wednesday, the reports say.

They left the bar and continued arguing at home, according to the records. The police reports say Dina Markham was locked out of the house, so she knocked on a window that one of their sons opened, letting her in. She went to the master bedroom looking for her keys, the reports say.

“The master bedroom was illuminated with ambient lighting and she observed Donald laying on the bed, on his side with his back towards her,” a police report says. “Dina continued looking for her key unsuccessfully. Dina felt the outside of Donald’s pockets, again looking for her keys and felt moisture on her hands. Dina realized the moisture was blood and called 911 for assistance.

“Upon further observations of Donald, it appeared that he had shot himself in the head.”

There is no indication in the police reports that Dina Markham or the kids heard the gunshot. That type of weapon is known to be relatively loud when fired under normal circumstances.

It’s unclear whether Donald Markham had his wife’s keys. But he did have her cell phone, according to police reports that say it was inside a pocket of her husband’s cargo shorts and was later retrieved from the Cook County morgue by Spain, who returned it to the widow.

At the time of her husband’s death, Dina Markham was assigned to the Internal Affairs Division. After the FBI began investigating, she was transferred to Area North, working for Cmdr. Kevin Duffin.

As the Area North commander, Duffin oversaw Walsh and the detectives who worked on Donald Markham’s case.

Duffin accessed those case files last June, about nine months after the case was closed and did so again in November and February, when he printed out the documents, records show. Ten days after Duffin accessed the records in February, Spain filed three “general progress reports” on Donald Markham’s death — 15 months after the case was closed.

Earlier this year, Dina Markham was reassigned to another unit, a police spokesman said.

Duffin would not speak with reporters. Spain said he’d have to check with a supervisor, then didn’t return calls.

While Duffin’s detectives investigated Donald Markham’s death, they aren’t investigating Dina Markham’s death. Her case has been assigned to detectives from Area South because Dina Markham once worked in Area North, according to police spokesman Anthony Guglielmi — “a precautionary measure to avoid any possible conflicts of interest.”

On May 22, Sun-Times reporters went to Dina Markham’s house and asked whether she was aware the FBI and inspector general were looking into her husband’s death. She said she wasn’t aware.

“I’d like to talk to you, but I’m not sure it’s in my best interest,” she said. “Give me a day to process this.”

The reporters returned on May 24, and she said she still needed to talk with “some people.”

“I have to protect myself,” she said. “I have to protect my children. That’s what this is all about.”

The following day, Friday, Dina Markham sent an email saying, “In respect for the way you approached me, a friend of a friend will be in contact with you. I am unsure who that will be at this time, but he assured me he will follow through. My family and I have been through very difficult times, and it has been awful especially for my children. Should you proceed in writing a news story, I would appreciate a ‘heads-up’ to prepare them.”

Dina and Donald Markham. | Facebook

Donald and Dina Markham got married in 1995. It was his second marriage. Their five children are between 13 and 27 years old.

Donald Markham, who had talked of retiring and had just sent a daughter to college shortly before his death, was a charming, fun-loving and hard-working guy, according to friends and family. He worked as a carpenter before becoming a cop and still worked carpentry side jobs.

Dina Markham was the daughter of a retired Chicago firefighter who owned a few neighborhood bars and also owned a video gambling business, according to public records. She had a small stake in the company, which supplies video poker machines to two suburban bars.

On Wednesday evening — after this story was published online — a Markham family attorney released a statement saying “our primary focus at this time is on Don and Dina’s five children” and asking that “everyone” respect the family’s need for privacy.

“While this article includes some information that may be accurate, there are many things presented that are inaccurate or incomplete,” the statement said. “Further, the family strongly refutes any suggestion, implication or allegation that Dina was responsible for Don’s death.

“With respect to any investigation that may have been pending, Dina had not been in contact with anyone conducting such investigation and only had heard rumors and third-hand accounts. We were trying to get information on this at the time of Dina’s death. Dina was prepared to address any question with the strength and resolve she is known for. As reflected in the email she sent to you, her sole focus was as it always has been — on the well being of her kids.”

The couple lived on a block with numerous other government workers, including a Cook County judge. The Markhams were known for throwing parties at their home, with its sprawling yard and in-ground pool.

tnovak@suntimes.com

rherguth@suntimes.com