Lawyers for the white Chicago police officer convicted of murder for fatally shooting black teenager Laquan McDonald say prosecutors have no right to challenge his nearly 7-year prison term.

Attorneys for Jason Van Dyke made the arguments in a filing Monday with the Illinois Supreme Court. They say the sentence is consistent with state law.

Illinois' attorney general and the case's special prosecutor have filed a petition to the high court, disputing the legal basis the judge used to sentence Van Dyke.

Van Dyke was convicted last year of second-degree murder and 16 aggravated battery counts. A judge sentenced him last month on just the second-degree murder conviction, ruling it was more serious.

Prosecutors want the 40-year-old sentenced on the aggravated battery counts, which could result in a longer prison term.