CHICAGO (CBS) — Former Chicago Police Officer Jason Van Dyke has dropped his appeal of his 2018 conviction for the murder of 17-year-old Laquan McDonald.

Van Dyke is serving a 6-year and 9-month sentence after a Cook County jury convicted him of second-degree murder and 16 counts of aggravated battery, one for each time he shot McDonald in October 2014.

Former Chicago police Officer Jason Van Dyke and his attorney Daniel Herbert listen during Van Dyke’s sentencing hearing at the Leighton Criminal Court Building, Friday, Jan. 18, 2019, in Chicago, for the 2014 shooting of Laquan McDonald. (Antonio Perez/Chicago Tribune via AP, Pool)

Van Dyke appealed his conviction, but on Friday, the Illinois Appellate Court agreed to dismiss his appeal, after his attorney filed a motion last month asking his appeal be dropped, according to Kane County State’s Attorney Joseph McMahon, who served as special prosecutor for Van Dyke’s trial.

“Mr. Van Dyke’s decision prevents additional years of litigation, bringing finality to the thorough prosecution of this case in which his rights were protected and justice was served. I wish to again thank everyone who diligently worked with us on this case from the time of our appointment as special prosecutor in August 2016 through today’s Appellate Court ruling,” McMahon said in a statement.

Van Dyke was the first Chicago police officer convicted of murder for an on-duty incident in more than 50 years.

Dashcam footage showing a Chicago police officer fatally shoot Laquan McDonald. (Source; Chicago police)

Dashboard camera video of the shooting shows McDonald walking down the street at 40th and Pulaski, holding a knife, before Van Dyke opens fire 16 times, as the teen appears to be moving away from him.

McMahon and Illinois Attorney General Kwame Raoul had asked the Illinois Supreme Court to order a new sentencing hearing for Van Dyke after he received only 81 months in prison, arguing it was improper for Judge Vincent Gaughan to sentence Van Dyke only for his conviction for second-degree murder and not for the 16 counts of aggravated battery, which they noted carry a longer minimum sentence.

However, the state’s highest court declined the petition for a re-sentencing.

Laquan McDonald (Supplied Photo)