LINCOLN, Neb. (AP) — The Nebraska Supreme Court has affirmed the conviction of a Guide Rock man who joined his mother in killing her boyfriend’s 68-year-old mother in 2013.

Andrew Casterline was found guilty in December 2014 of first-degree murder, burglary and a weapons crime in the October 2013 slaying of Virginia Barone. His mother, Shelley Casterline, also was convicted of murder and sentenced to life in prison.

Andrew Casterline argued in his appeal that the evidence was insufficient to convict him and that a district judge erred in allowing some evidence and in using certain language in jury instructions.

The high court disagreed with his assertions in its ruling issued Friday.

His mother lost her own appeal to the Supreme Court last May.