LOUISVILLE, Ky. (WDRB) -- Metro Police say they've solved a 42-year-old cold case murder involving a 1-year old, but  65-year-old suspect, Lawrence Beck, is not behind bars at Metro Corrections.

He was indicted by a Jefferson County grand jury on Tuesday and arrested a short time later by Los Angeles Police. Detectives at Metro Police headquarters say he committed the crime in 1971.

"He was in a step-father role," says Diane Arnold, Assistant Commonwealth's Attorney. She says Beck is responsible for the death of his then girlfriend's son, 20-month old Michael Sanders.

Police say it happened in December of 1971 inside apartments on Kingston in the south end of Louisville.

"It was a shaken baby and as well as injuries to his body," Arnold explains. Since then, Beck has moved across the country, but detectives never stopped working the case.

"It says a lot about LMPD that none of the cases are going to be put by the wayside, they want to make sure that they find who did this so that we can get justice for this little boy and the family."

Arnold explains why, in this case, justice and Beck's arrest were delayed. "Something really important to this case is the advancement of pediatric forensic medicine." Those advancements led to Beck's arrest. 

"Knowing about our body system has really made us be able to look at what happened to this child and figure out what did happen to him."

The indictment says point blank, that Beck "Killed a child under his care." Both police and prosecutors feel confident they have the right suspect.

"We would never indict a case if we didn't have enough evidence for the grand jury to indict," Arnold says.

Lawrence Beck was actually arrested near his home in Los Angeles on Tuesday.

He is being held on a half-million dollar bond and is expected to be extradited back to Louisville in the next few weeks.

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