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Texas man sentenced to 44 years in prison in connection with 2017 Idaho/Colorado murder mystery - Ada County Sheriff

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Texas man sentenced to 44 years in prison in connection with 2017 Idaho/Colorado murder mystery

When deputy Tim Cooper pulled over a 27-year-old man for erratic driving on Interstate 84 last September, he didn’t realize he was about to unlock a disturbing murder mystery over 800 miles away.

A year and a half later, we have a few more answers – but still don’t know exactly why Jeffrey Maynard killed John Cumby Jr. in rural Colorado, stole his van (and all his belongings), and drove to Idaho.

What we do know is Maynard has admitted to killing the 63-year-old Cumby – and will spend up to 44 years in prison for the murder.

The case was resolved thanks to some excellent investigative work in two states — by Cooper and other members of the Ada County Sheriff’s Office Criminal Investigation Division here in Idaho, and by law enforcement in Gilpin and Jefferson counties in Colorado.

When Cooper pulled Maynard over for cutting off a semi and driving between 40-to-60 mph on I-84 on Sept. 10, 2017, Maynard didn’t have a driver’s license or any kind of identification at all – and couldn’t explain why he was driving a van filled with someone else’s stuff.

In just a short amount of time, while pulled off on the side of I-84, Cooper was able to determine who Maynard was, that he had two active arrest warrants out of Texas, figure out the van actually belonged to John Cumby, figure out Cumby was reported missing by his family almost two weeks before, and make contact with several of Cumby’s family members trying to figure out what was going on.

When talking to Cumby’s family, Cooper found out Cumby left Illinois to go camping in Colorado in August — and family members hadn’t heard from him at all for about two weeks. Maynard then told Cooper he had just been camping with Cumby in Colorado but didn’t know where he was.

Deputies then brought Maynard back to our station and interviewed him. He was lucid until asked about Cumby. Then Maynard would act confused or say he didn’t know where Cumby was.

Detectives used information gathered from Cumby’s van and cell phone, including pictures, to find his last known location – a campground near Rollinsville, Colorado.

Ada County Sheriff’s investigators also found evidence Maynard did internet searches for topics including “How to plead insanity,” “how to act insane,” “fake being insane,” “how people who fake insanity give themselves away,” and “10 uses of insanity defenses” – searches detectives later determined were done right after Cumby’s death.

Detectives called Gilpin County Sheriff’s Office detectives and explained what was going on. Colorado investigators found Cumby’s body near the campground, covered in debris, on Sept. 13, 2017.

Maynard stayed in the Ada County Jail for a few months before transferring to jail in Gilpin County, Colorado, where he was charged with murder.

Maynard eventually pleaded guilty to second-degree murder, identity theft, and aggravated motor vehicle theft  in connection with the case earlier this fall.

He will have to spend at least the next 33 years in prison before he can ask for parole.

We are just glad Deputy Cooper was patrolling I-84 that day — and doggedly pursued the truth until he figured out what was going on. Had he not been out there, who knows when the crime would have discovered?

Thanks to that effort, the Cumby family knows what happened, and the man responsible won’t be able to harm anyone else for at least the next three decades.