Suspect in teen’s murder mystery announced 4 decades after slaying

ATKINSON, Illinois - Almost 43 years to the day of an Atkinson, Illinois teenager's murder, authorities today revealed the name of the man they believe is the killer.

Mary Ann Becker, 16, was found strangled in the living room of her family's home on September 9, 1974.  She had been tied to a piano, and an electrical cord found near the body.

Over the past 4 years, Illinois State Police launched a renewed effort to solve the decades- old mystery, including the exhumation of the young woman's body from St. Anthony Catholic Cemetery in Atkinson.

Today, the Henry County State's Attorney's office named the late Robert Clark as the likely suspect in the the cold case. He died in March of 2015 in Bloomington, Indiana.

Robert G Clark, 1970s (left), 2013

"Upon reviewing the thousands of pages of new interviews, the State's Attorney believes the circumstantial evidence is strong enough that it would warrant presentation to a grand jury if Mr. Clark were still alive," said Matt Schutte, Henry Count State's Attorney.

Clark, who would have been 24 years old at the time of the murder, lived alone in an apartment near the Becker's house. He worked with Mary Ann's father Tony at the local coal mines.

Police say when Clark was initially interviewed shortly after the crime, he had insisted he was at work that night, and had been busy hauling loads of coal the evening of the murder.

Investigators recently discovered "new information contradicting the alibi that Clark was working in the Victoria Coal Mines at the time of the crime."

They say Clark's brother revealed that Clark had confided in him that "he was not working at the time of the murder."

Over the past few years, investigators traveled to five states conducting more than 100 interviews with family members, friends, neighbors, co-workers, and current and former Atkinson residents.

"As the investigation progressed, Robert Clark could not be excluded and rose to be the strongest person of interest in the case," according to the news release.

Clark was later convicted of raping a 15-year-old girl in Galva, Illinois. According to the press release, he was sentenced to 6 years in prison, but only served two days in the county jail after winning an appeal in a higher court.

The news release states the two man investigative team assigned to the cold case in 2013, uncovered new information from witnesses who were either not spoken with during the initial investigation, or remained silent out of fear.

"The two man investigative team located several people connected to Clark over the years and documented a consistent pattern of violent criminal behavior and mental illness spanning Clark's entire adult life. Several people from Clark's past were reluctant to speak about him until after they learned he was deceased. By the late 1980's, Clark had been married and divorced three times. During one of many violent attacks against his second wife, Clark reportedly stated he had killed before and would do it again. Clark threatened to bury her body in the coal mine."

On September 29th, 2014, Mary Ann's body was exhumed with the hope of collecting physical evidence for DNA, not available in 1974.

It was a long shot, and the results were unsuccessful in developing a full suspect DNA profile, because of deterioration of the victim's body.

Vandemore Funeral homes, owned by Joel Vandemore, stepped in and provided a new casket, private ceremony, and reburial, free of charge.

Illinois State Police and the Henry County State's Attorney's office are releasing their findings just days before the 43rd anniversary of the murder, hoping someone comes forward with even more information to confirm their belief that Clark is the perpetrator of the crime that shocked the small town of 1,100.

Meanwhile, Mary Ann's family is withdrawing their $15,000 reward, "confident" enough the responsible person has been identified.

According to news reports at the time, Mary Ann was a "shy and quiet type of girl", an "A student at Atkinson High School."

The unsolved murder was the oldest cold case on the Illinois State Police's Unsolved Crimes web page.

Click here to read the original news release