Little information about the teenager's status has been available because Utah law in most circumstances prohibits the release of information on children in the juvenile court system who are younger than 14.
But Salt Lake County District Attorney Lohra Miller discussed the boy's sentencing at a Glendale Community Council Meeting on Wednesday after she was asked by residents about the boy's punishment.
The teenager was convicted of the crime and can be held at a juvenile detention center until he is 21, Miller said.
Police say 49-year-old Wally Knapton was shot and killed March 12 during a robbery attempt at the Family Dollar store where he worked, at 1145 S. Glendale Drive.
Biu Olive, an 18-year-old who police say is a member of the Tongan Crip Gang, and Sarah Ataata, 19, the suspected getaway driver, were also charged in connection with Knapton's murder.
Olive and Ataata are to appear in court for a scheduling hearing on Aug. 1 before Judge Judith Atherton.


