Karen Benjamin was hit while jogging in Mount Sinai last month.
Investigators say a small piece of the car left the scene lead to the arrest.
31-year-old Thomas Costa tried to hide his face as he left the Suffolk County District Attorney's office Wednesday morning in handcuffs.
But in court, there was no hiding from the family of Karen Benjamin.
"I hope he rots in his jail cell," said Lindsay Benjamin, the victim's daughter.
Benjamin's daughters and her entire family were there to see Costa's face.
He's accused of running into the 56-year-old while she was jogging on a Sunday morning last month in Mount Sinai.
Benjamin was in a coma for three and a half weeks until she died July 17th.
Costa allegedly hit her so hard it knocked the side view mirror off his car.
Police spent night and day canvassing the area looking for a car with similar damage.
And they found it in the back of Costa's parent's house nearby.
"He had showed up to his parents' house about 15 minutes after the incident occurred and that's when he told his parents that his car had been vandalized at a night club in Patchogue," Suffolk County District Attorney Thomas Spota said.
But on the side of it was blood.
Prosecutors say DNA testing has concluded its Benjamin's blood.
"We're heartbroken, nothing can bring her back. We want to know why this person did this. Was he high, was he drunk, was he not paying attention?" said Bob Freedman, the victim's brother.
