WOBURN – A New York man has been sentenced after pleaded guilty to murder charges in connection with the shooting death of Justin Cosby, 21, of Cambridge, Middlesex District Attorney Gerry Leone informed the public today. Jason Aquino, 21, of Manhattan, New York, pleaded guilty on March 24 in Middlesex Superior Court to charges of manslaughter, and willfully misleading a Grand Jury. Today, Middlesex Superior Court Judge Howard Whitehead sentenced the defendant to 18 to 20 years in state prison on the manslaughter charge and 4 to 5 years in state prison on the willfully misleading a Grand Jury charge. “On behalf of Justin, his mother and sister, his entire family and circle of friends, we continue to hold all those accountable for the killing of Justin Cosby,” District Attorney Leone said. “Our efforts continue as we turn our attention to the sentencing of Blayn Jiggetts, and the trial of Brittany Smith.” According to authorities, on Monday, May 18, 2009 at approximately 4:48 p....