The results of toxicology tests were the final factor in an investigation that produced summonses but no criminal charges against both drivers.
The cars were both headed east toward Haverstraw just before midnight Sept. 8 when the crash occurred between Wilder and Spook Rock roads, Chief Brad Weidel said.
One of them, a 2008 Honda driven by 19-year-old Tzvi Hakakian of Monsey, was "slowing in the roadway to possibly turn left into a driveway," Weidel said.
The other, a 2016 Lexus driven by 24-year-old Jonathan Mosquera of Suffern, "attempted to go around the Honda on the left side," the chief said.
The vehicles sideswiped one another, after which the Honda continued east and the Lexus veered left, crossing the westbound lane -- where it struck two pedestrians who were standing near the edge of the same driveway, Weidel said.
The Lexis then hit a guard rail and rolled down an embankment, hitting a number of trees along the way to the bottom, he said.
One of the bystanders, 17-year-old Marcos Tawil, was taken to Good Samaritan Hospital, where he was pronounced dead shortly after arriving, Weidel said.
The other, David Maldanado, was taken to Westchester Medical Center in serious condition, he said.
Weidel said Friday that there was "no evidence to indicate that drugs and or alcohol were a contributing factor on behalf of either driver in this accident."
However, he said, Hakakian "moved from his lane of travel unsafely and was making an improper left turn on a two-way roadway," while Mosquera was "traveling at a speed not reasonable and prudent, as well as speeding in zone.
"Mosquera also moved from his lane of travel unsafely and improperly passed a vehicle," the chief said.
"The contact occurred while both vehicles were in the improper lane," he said.
Police issued four summonses to Mosquera -- for speeding, for speed that "was not reasonable and prudent," for moving from a lane unsafely and for improper passing.
Hakakian received summonses for moving from a lane unsafely and making an improper left turn onto a two-way roadway.
All the summonses are returnable in February in Wesley Hills Justice Court, the chief said.
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