In a May 7, 2013, file photo, Charles Anthony "Tony" Nelson, foreground, and Brody Blu Kruckenburg, background, appear in 7th District Court in Moab, Utah. Nelson, who prosecutors say helped get rid of the body of the body of a friend's mother's boyfriend, has been sentenced Monday, Sept. 9, 2013, to the highest-security juvenile detention facility. (AP Photo/Deseret News, Geoff Liesik, File)

A Moab teenager who prosecutors say helped get rid of the body of the body of a friend’s mother’s boyfriend has been sentenced to the highest-security juvenile detention facility.

A juvenile court judge delivered the sentence on Monday to Charles Anthony Nelson, 17, following a psychological assessment, said Grand County Attorney Andrew Fitzgerald. A probation board will determine whether he will stay behind bars until he turns 21 or gets out earlier.

Nelson will likely spend less time locked up than his friend, Brody Blu Kruckenberg, 17, who confessed to the March 25 murder of Gregorio Salazar Campos.

Prosecutors initially believed Nelson shot Gregorio Salazar Campos three times in the head on March 25 in Moab because Nelson was bragging about pulling the trigger to friends. But detectives later learned it was Kruckenberg who shot Campos.

Salazar was dating Kruckenberg’s mother.

Prosecutors believe rival drug dealers of the victim pressured Kruckenberg into the murder. Fitzgerald said they spotted a troubled and impressionable young man who shared their disdain for Salazar. The adults owed Salazar money and were upset that he was lacing the drugs he sold with chemicals that were making people sick, Fitzgerald said.

Fitzgerald said on Monday that prosecutors in the southeastern Utah county still expect to file charges against the three to four adults for their role in influencing Kruckenberg, Fitzgerald said.

In July, Kruckenberg pleaded guilty to manslaughter in exchange for having his case moved to juvenile court from adult court. He was sentenced to high-security juvenile detention until he turns 21.

Prosecutors have also reduced charges Nelson, who agreed to the charge of obstruction of justice. His case was also moved to juvenile court.

Kruckenberg’s mother, Corina Dawn Yardley, 44, pleaded guilty to two counts of obstructing justice earlier this month. She was sentenced to 90 days in jail.