TULSA, Oklahoma - A judge made a ruling Friday on whether prosecutors can have their own expert perform a mental evaluation of Michael Bever, a teenager charged with killing his parents and some of his siblings.

The judge ruled Bever can be interviewed by the state's mental health expert.

But he can keep his fifth amendment rights, so when the expert asks him questions about the day his parents and three siblings were murdered he does not have to say anything.

Judge Holmes referenced several cases in making her decision.

District attorney Steve Kunzweiler says the judge's decision allows us to learn more about Michael’s mental health but says they need to know if he understood the consequences of his actions before the 2015 mass murder.

The defense says the judge made the right call and that everyone deserves their fifth amendment right rights, even Michael.

His brother, 21-year-old Robert, pleaded guilty and is already serving five life sentences.

Michael will be back in court for another hearing January 5th.