SPRINGFIELD — The Illinois Supreme Court denied the state’s petition for a writ of mandamus to change Jason Van Dyke’s 81-month sentence for the murder of Laquan McDonald.Four justices voted to deny the mandamus request, including Justice Thomas L. Kilbride, who also wrote a partial dissent.Justice P. Scott Neville Jr. dissented from the majority, and Justice Mary Jane Theis took no part in the decision.Illinois Attorney General Kwame Y. Raoul and Kane County State’s Attorney Joseph H. McMahon …