A group of youths piled into two vehicles to go swimming. One was operated by 19-year-old Monica Mendoza, with her younger sister as a passenger; the other, by D, a 17-year-old with a junior 'class DJ' license. D was driving a 2004 Mercury Mountaineer, a midsized SUV; the Mountaineer had no mechanical defects and nearly new tires. D was transporting four teenage passengers; none were family members. Ae holder of a class DJ license may not operate a vehicle with more than two passengers under 21 years of age who are not members of the junior licensee's immediate family and must ensure that all passengers have buckled their seat belts. None of D's four passengers--a 14-year-old, a 15-year-old, a 17-year-old and an 18-year-old--wore a seat belt. D did. The posted speed limit was 55 miles per hour. Monica 'slowed down' her car because she was 'not always used to driving' that type of hilly, winding road. When she reduced her speed, D 'just kept on the same speed. Monica saw D lose control of the SUV. Three of the passengers died in the accident, and one was critically injured. D suffered noncritical injuries. He tested free of drugs and alcohol. The only surviving passenger testified at trial, and the first time he noticed anything distinctive about D's driving was when he 'felt the car lose control' and 'felt the back end slide . . . [and] hit the dirt on the opposite side of the road.' A Deputy authored a police accident report concluding that the operator of vehicle one at a rate of speed unsatisfactory for the roadway and failed to negotiate a curve. When D's vehicle went off the left-hand side of the road, it slid down a 25-to-30-foot embankment. The Deputy knew of other accidents at this location. Detective Don Starner had 'investigated several accidents . . . most of them caused by either speed and or alcohol' on Sackett Lake Road near the crash site. Trooper Conklin, a collision reconstructionist for the New York State Police, concluded that the tire marks from D's vehicle were made by 'critical speed yaw.' This occurs when a vehicle begins spinning on its central axis, and the tires are 'side-slipping' while rotating; in other words, the tire marks were caused by the vehicle as it spun out of control, not by skidding upon braking. Conklin calculated a speed of 70-72 miles per hour upon entry into the critical speed yaw and opined that the left side of D's vehicle had crossed the double-yellow center line by that point. Conklin concluded that the vehicle was attempting to negotiate the curve at a speed that was too great to be negotiated causing the SUV to enter into critical speed yaw. He observed that once critical speed yaw is entered, 'it is very difficult to bring the car back under control.' D was charged with three counts of criminally negligent homicide, assault, and reckless driving. D contends his actions were insufficient as a matter of law to establish criminal negligence. D also contends that excessive speed is by itself not enough to support criminal negligence, and that junior license violations are not evidence of criminal negligence. D objected to the judge's main and supplemental jury charges. D was convicted and served out his sentence in a maximum security prison. D appealed.