MINNEAPOLIS (AP) — The Minnesota Supreme Court has ruled a convicted murderer must be sentenced again because an “aggravating factor” was improperly considered during his initial sentencing.

Raymond Clyde Robideau was earlier sentenced to 38 years in prison for fatally stabbing his girlfriend, Sharon Chouinard, in their East Bethel home in January 2008. Robideau received nearly 8 years beyond the state guidelines, in part because the crime was committed in the presence of a child.

In an order published Thursday, the Supreme Court said the victim’s 14-year-old son was in the house when his mother was killed, but didn’t see or hear her murder. Therefore, the high court says that aggravated factor didn’t exist and shouldn’t have been considered.

The Star Tribune says Robideau will be re-sentenced in Anoka County District Court. A date wasn’t immediately set.