The second driver in a 2007 car race and crash that killed a young Mililani woman pleaded guilty yesterday to leaving the scene of a fatal accident and second-degree assault.

Under a plea agreement reached with prosecutors, Bernard DeCoito Jr. will be sentenced to 18 months in prison and five years of probation.

The other driver, Justin Amorin, 24, was convicted in a jury trial last year of negligent homicide and assault and is now serving a 10-year prison sentence.

The two were racing on residential streets in Mililani at speeds above 100 mph when Amorin's car smashed into a tree, killing passenger Gillian Badua, 17, and permanently disabling another passenger, Gavin Watson.

Deputy Prosecutor Sean Sanada said DeCoito "did admit that they were driving erratically, he did admit that there was not a chase, that they were just doing foolish things and that's why this happened.

"He did not directly cause the collision per se, but he did leave the scene, he did leave his friends there to die," Sanada said.

If DeCoito misbehaves on probation, he will be subject to an open term of imprisonment of 10 years, Sanada said.