(CNN) Cook County State's Attorney Anita Alvarez has taken herself and her staff off the murder case against the police officer accused of wrongly killing Chicago teenager Laquan McDonald.

Gaughan said he would announce his decision on June 2. At a hearing Thursday, Alvarez asked Judge Vincent Michael Gaughan to appoint a special prosecutor in the case against Officer Jason Van Dyke Gaughan said he would announce his decision on June 2.

"My primary goal in bringing a charge of first-degree murder in this case is and always has been about seeking justice for Laquan McDonald," Alvarez said in a statement. "Today I believe that I am fulfilling this obligation by requesting that the court turn this case over to a special prosecutor.

"While it has not been an easy decision, I believe that it is the right one because it will help to avoid unnecessary legal delays and provide continuity in the handling of this very important and complicated case," she said.

Alvarez lost the Democratic primary for state's attorney in March so she would likely not be in office throughout the high-profile case. She had faced heavy criticism over her handling of the case.