By David DeKok
HARRISBURG, Pa. (Reuters) - A Pennsylvania teenager pleaded guilty on Thursday to first-degree murder in the killing of her mother last year and was sentenced to spend at least 35 years in prison after agreeing to testify against her former boyfriend, prosecutors said.
Jamie Silvonek, 14, of Upper Macungie Township outside Allentown, appeared before Lehigh County Judge Maria L. Dantos, entered her plea, and was immediately sentenced to 35 years to life in prison, the Lehigh County district attorney's office said in a press statement.
The district attorney's office said it could make no further comment because a gag order issued by the court was still in effect. Silvonek’s lawyer, John Waldron of Allentown, did not return a call seeking comment.
Silvonek agreed to cooperate in the prosecution of her co-defendant and former boyfriend Caleb Barnes, 21, a soldier from El Paso, Texas, who was stationed at Fort Meade, Maryland. He is scheduled to go on trial April 16., according to the statement.
The girl, then 13, had met Barnes, then 20, at a concert in Philadelphia, but told him she was 16. In the months that followed, they developed an online relationship that soon became sexual, authorities said.
Her mother, Cheryl Silvonek, 54, tried to break up the relationship when she learned Barnes was 20. Authorities said the two began plotting by text to kill her, with Jamie Silvonek urging Barnes to do it.
Despite her misgivings about Barnes, Cheryl Silvonek agreed to drive the couple to a concert in Scranton on the night of March 14. When she returned home with the couple at 1 a.m. on March 15, Barnes grabbed the mother from behind, choked her, and slashed and stabbed her in the neck until she died, authorities said.
They buried the body in a shallow grave several miles from the house but were spotted by a neighbor, which led to their arrest. Police found the bloody car, then found Silvonek and Barnes naked in bed together at her home.
Jeffrey Dimmig, senior deputy district attorney, said prosecutors deemed a minimum sentence of 35 years as appropriate for Silvonek because of the degree of criminal sophistication she displayed, among other factors.
After the 2012 U.S. Supreme Court ruling barring mandatory life sentences for juveniles, Pennsylvania enacted a law requiring either a life sentence for juveniles under 15 who commit first-degree murder, or a sentence of at least 25 years to life imprisonment.
(Reporting By Frank McGurty; Editing by Toni Reinhold)