The parents say they had no intention of suing but felt forced to when the county went back on their promise to investigate.
Isabella Grasso was a 17-year-old on her way to achieving big things; honor student, ballet, and actress.
Weeks after taping an episode of "Law and Order", the Long Island teenager with all the promise and talent parents could hope for died in a car crash.
"I don't understand what happened, why weren't any of the protocols followed?" said Linda Grasso, Isabella's mother.
The Grasso's are convinced their daughter would still be alive today had it not taken Nassau County's Police medical helicopter so long to get her to a trauma center.
Police records show an ambulance arrived on the scene that morning just 5 minutes after the accident.
But a decision was made to airlift her.
County police have refused to release the helicopter response times, but what we do know is Isabella arrived at the hospital at 8:17.
That's 46 minutes after EMS first arrived at the accident scene.
"Why was there a delay? What was the delay about? And why, if there was a delay, did they not use common sense and take her to a hospital in an ambulance," said Michael Grasso, Isabella's father.
Eyewitness News wanted to see how long it would take us to drive to the trauma center from the accident scene.
It was 7:31 in the morning around the time of the accident.
Eyewitness News used a stopwatch to time the trip.
It's a 15 mile drive to the hospital in which we drove without sirens .
Eyewitness News arrived at the trauma center in 27 minutes, 52 seconds.
That's more than 18 minutes faster than it took to get her to the same trauma center by helicopter which means they directly violated their own airlift protocols.
The County Air Medical guidelines specifically state, "A patient is to be air-lifted to a trauma center when transportation time "can be decreased by more than 15 minutes".
"Time is important. The longer you wait, the faster they bleed," said Juan Delgado, Medevac Foundation.
Juan Delgado of the Medevac Foundation has spent 15 years flying in air medical units.
"Essentially, if you're 30 minutes or less from a trauma center you want to go by ground," Delgado said.
But with Isabella bleeding internally, the decision is made to wait for the helicopter which is delayed.
But why, perhaps the crew got caught in a shift-change.
Overnight, the medics and pilot are ''on call" from their homes.
It's not until 7:30 in the morning (around the time of the accident) that a crew is actually on site at the County Police Air Medical Unit:
"The overwhelming majority of medical aircraft are staffed 24 hours a day," Delgado said.
"The crew is right there?" Eyewitness News investigative reporter Jim Hoffer asked.
"Crew and pilot are on-site with the aircraft," Delgado said.
"Why is that critical?" Hoffer asked.
"With everybody in one location, the aircraft's launch is not delayed," Delgado said.
"The delays absolutely cost my daughter her life. Absolutely," Grasso said.
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