One of two Oklahoma brothers accused in the stabbing deaths of their parents and three siblings is challenging the constitutionality of a state law that says he must be charged as an adult.

The Oklahoma Court of Criminal Appeals will hear oral arguments on Thursday in the case of 17-year-old Michael Bever.

Bever and his 19-year-old brother, Robert Bever, are charged in Tulsa County with five counts of first-degree murder in the July attack that killed their parents and siblings, the youngest of whom was 5.

Michael Bever, who was 16 at the time of the deaths, is challenging a special judge's ruling that rejected a request by defense attorneys to certify him as a juvenile delinquent or youthful offender.

A preliminary hearing for the brothers is set Feb. 23.