Fifteen years ago, Chicago police Officer Eric J. Elkins was charged with having sex with a 16-year-old boy he befriended while moonlighting as a high school security guard — a case for which he was cleared by a judge and never faced any punishment by the police department.

Elkins has continued to have troubles, but he’s received no disciplinary action from the department, according to a Chicago Sun-Times investigation that found:

• Three years ago, he was accused of touching the penis of a teenager during a family reunion near Elkins’ boyhood home in rural Michigan. He ended up pleading guilty in 2016 to a lesser charge, avoiding prison and sex-offender registration.

• Elkins completed his sentence — including a year of probation — last year. But the Chicago Police Department says its internal affairs bureau still hasn’t finished investigating whether Elkins should be disciplined or fired.

• Now, Elkins is being investigated by his own department over two additional matters: what a police source says is another “sexual related incident,” as well as an off-duty fight last month in which one man suffered a broken ankle and another broken cheekbones outside a North Side bar. Records show Elkins left the scene of the fight before responding officers arrived.

Elkins, 44, who is now a sergeant, has been on desk duty since the Michigan incident.

While awaiting the conclusion of that disciplinary case, he has gotten two union-mandated pay raises, which totaled about $4,000 a year, records show. His salary is now more than $104,000 a year.

And his retirement benefits have grown to where he’d be entitled to a pension of about $75,000 a year, provided he reaches his 20-year departmental anniversary in December 2019.

Police spokesman Anthony Guglielmi says the internal affairs investigation of the incident in northeastern Michigan has taken more than three years in part because internal affairs investigators had to wait for the criminal case to be wrapped up. Also, Guglielmi says, any witnesses live hundreds of miles away.

Internal affairs investigators didn’t interview Elkins about the Michigan incident, though, until after Sun-Times reporters first asked the department about him last month, according to a source.

But Guglielmi says, “It wasn’t forgotten.”

Two months ago, the Sun-Times reported that another Chicago cop, Lt. Gerald Breimon, remained on the job after being accused of fondling a woman he told he needed to frisk for weapons during a traffic stop 15 years ago and of later demanding sex from another woman — a fellow cop — and threatening to ruin her career if she didn’t comply.

The Michigan investigation of Elkins involves a family reunion near his boyhood home in rural Ogemaw County on the Fourth of July in 2015. Records obtained by the Sun-Times show Elkins ended up “pretty intoxicated,” to the point that a cousin told police he was concerned Elkins might “stumble” into a bonfire.

According to Michigan State Police records, Elkins touched the genitals or buttocks of four teenage boys at the party over their clothes and engaged in “vulgar” talk with the boys, who’d been curious about his job as a cop in Chicago.

The Michigan records show the boys then “went to their tents and got their pocket knives in case Eric came around them again.”

After adults at the party learned that the boys were frightened by what happened, Elkins was told to leave, the records show.

Several guests at the party who are related to Elkins said they didn’t believe the accusations, suggesting that one of the boys’ parents called the police in hopes of getting a future payout from a lawsuit against Elkins.

Elkins told the Sun-Times no money ever changed hands.

The parents of one of the boys — who told authorities Elkins touched his penis — pursued charges against the cop.

Four months later, the sex charge was dropped when Elkins agreed to plead guilty to the other charges. He was sentenced to one year of probation and ordered not to enter any business serving alcohol by the glass. He also was ordered to enroll in a substance-abuse program and do 80 hours of community service, court records show.

Elkins downplays the criminal case he faced in Michigan, saying, “It was simple assault.”

Shortly after the incident, the police department put Elkins on desk duty. He is assigned to the city’s 311 non-emergency call center.

Previously, he had been indicted by a Cook County grand jury in July 2003, accused of carrying on a sexual relationship with a teenage boy who was a student at Amundsen High School in Ravenswood. According to court records, they would meet at the boy’s locker and then engage in sexual contact that included oral and anal sex, in one instance in a bathroom at the high school.

The student — an immigrant who had moved to Chicago with his parents less than five months before meeting Elkins — drew a detailed map for the police of Elkins’ apartment in Andersonville. He told the police he would call Elkins from pay phones. Detectives found the numbers for those pay phones when they searched Elkins’ phone records, court files show.

Police reports filed by the officers who went to Elkins’ apartment to talk to him about the allegations say that when they told him why they were there, “Elkins then stated, ‘He came on to me’ and further responded, ‘I had contact with him.’ ”

The reports don’t say what that contact was.

According to those reports, Elkins told other officers “that he was trying to set up [the teen] with a family friend . . . who was gay and 18 years old. He stated that he has been friends with [him] about 10 years and that he lives in Michigan.”

Elkins went to trial but was found “not guilty” in June 2004 by Cook County Circuit Judge Kenneth Wadas, who says now that he didn’t “think the victim was credible” and that the “state did not meet the burden of proof.”

The student, now an adult, declined to comment.

His former principal Pauline Tarvardian says she was shocked when the allegations were made against Elkins, who was then a 29-year-old cop also working as a Chicago Public Schools security guard.

“I thought it was a mistake,” Tarvardian says, because Elkins came across as so professional and dependable. But the former Amundsen principal says the student “seems credible . . . He knew too much, like all the rooms in his apartment.”

Elkins says he was wrongly accused.

“The judge was very clear that this person wasn’t truthful,” says Elkins, who later was promoted, first to detective and then to sergeant.

In 19 years with the Chicago Police Department, Elkins has faced 35 internal investigations, police records show. Two of those cases — one involving the Michigan incident, the other the bar fight — are still pending. The other 33 were closed without any disciplinary action, the records show.

The department would not discuss what the police source calls another “sexual related incident.”

And Elkins is under internal investigation for failing to notify the police department “he was involved in a physical altercation” on Sept. 29 at the Atmosphere Bar in Andersonville while off duty, records show.

Two men told the police they were leaving the bar when they were knocked down and repeatedly kicked, leaving one with a broken nose and broken cheekbones and the other with a fractured ankle. Two men ran away but were quickly caught by police and charged with battery. Other than being “involved,” the records don’t say what role Elkins had in the incident.

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