CHIPPEWA FALLS — The Wisconsin Court of Appeals will determine whether the teenage boy charged in the killing of 10-year-old Lily Peters remains in adult court or if the matter will revert to a juvenile proceeding.

The teen, who turned 16 in March, is charged with first-degree intentional homicide and two counts of sexual assault in the death of 10-year-old Peters on April 24, 2022, in Chippewa Falls, Wis. Her body was found the next morning. He has been identified in court only by initials, and has been held in the Northwest Regional Juvenile Detention Center in Eau Claire on a $1 million cash bond since his arrest.

Attorneys for the teen have sought a reverse waiver, which would move the case to juvenile court. The motion was denied, but the Court of Appeals agreed in February to review the ruling.

Defense attorney Michael Cohen filed a 35-page brief to the Wisconsin Court of Appeals last week, arguing that the Circuit Court was wrong in concluding the case should be tried in adult court.

"The Circuit Court correctly found that he could not receive adequate treatment in the criminal justice system and that retaining jurisdiction in adult court is not necessary to deter him or other juveniles, but the Circuit Court erred in finding that transferring jurisdiction would depreciate the seriousness of the offense," Cohen wrote.

Cohen also contends a lengthy prison sentence isn't warranted as a deterrent to others.

Wisconsin Attorney General Josh Kaul and Assistant AG John Flynn submitted a 25-page response Monday, arguing that the Circuit Court "properly exercised its discretion when it denied [the teen's] petition for reverse waiver." The attorney general's office also challenged a claim that keeping the case in adult court is about retribution.

Chippewa County District Attorney Wade Newell estimated Monday that the Court of Appeals will announce its decision in about four weeks, although he stressed that is a guess.

The reverse waiver hearing was held last August. Judge Steven Gibbs ruled on Jan. 22 that the case would remain in adult court, rejecting the defense's petition. In his ruling, Gibbs said allowing the teen the ability to walk free when he turns 25 depreciates the seriousness of the offense.

Cohen then filed his appeal, asking the higher court to reconsider the reverse waiver ruling.

No trial dates have been set. Gibbs had previously said he would not set any further court dates in the matter until the Court of Appeals decides.