Accused Ashland County serial killer Shawn Grate Wednesday changed his plea to guilty on 15 of the 23 charges against him. RichlandSource.com reports, Grate plead guilty to rape, abuse of a corpse, tampering with evidence, burglary and kidnapping. Sentencing will take place after the jury’s verdict comes in on the 4 counts of aggravated murder, which could send Grate to prison for 50 – 72 years.