CHICAGO (CBS) — Gov. Bruce Rauner said Monday he’s “very disappointed” in how Mayor Rahm Emanuel and Cook County State’s Attorney Anita Alvarez handled the investigation into the fatal police shooting of 17-year-old Laquan McDonald.

McDonald was shot 16 times by Officer Jason Van Dyke in October 2014. Officers were responding to calls about a person slashing tires, and McDonald had ignored orders to drop a small knife he was carrying, but dashboard camera video of the shooting showed McDonald was walking away from officers at the time he was shot, and the video disputes initial claims by police that he lunged at police with the knife. Emanuel fought for more than a year to keep the video of the shooting under wraps, and Alvarez took more than a year to file murder charges against Van Dyke.

“I am very disappointed in the mayor and in the state’s attorney for Cook County; very disappointed. I’m not going to say more than that right now, because there’s a lot of investigation going on, but I’m very disappointed,” Rauner said Monday at an unrelated event.

It’s not the first time Rauner has addressed the Laquan McDonald scandal. Last month, Rauner said he cried when he saw the video of the teen’s death, calling it “shocking [and] terrifying.”

“I cried for the young man who was brutally shot; cried for the thousands of police officers who are honest and hard-working, put themselves in harm’s way to preserve and protect us, and whose reputation gets damaged by the behavior of a few bad people; cried for the violence that is tearing apart so many of our communities,” the governor said.

As many protesters have, Rauner in December questioned why it took more than a year to file murder charges against Van Dyke.

“Anybody who sees that video has to really wonder why would it take so long to prosecute or deal with this. What’s taken so long? It’s a legitimate question for everybody to be asking,” he said at the time.

In response, an Emanuel spokesperson said: “The mayor’s focus in not on his own personal politics. His focus is on taking the action necessary to finally and fully reform the system and culture of policing in Chicago.”

Though Rauner would not elaborate on why he is disappointed in Alvarez and Emanuel, he said, if approved by the legislature, he would sign a measure allowing Chicago voters to recall a future mayor.

State Rep. La Shawn Ford (D-Chicago) has introduced proposed legislation that would set up a recall process for the mayor of Chicago, but it has not yet been assigned to a committee, and Rauner said his legal team has said any recall measure could not apply to sitting elected officials, only future elected officials.

U.S. Sen. Dick Durbin, at a separate appearance Monday, did not reject the idea of recall.

“I’m going to leave it to the people of the General Assembly to debate that,” Durbin said.