The team tries to determine who was driving. Jesse says they are looking for fiber plastic fusions that occurred during the crash. After analysis they determine that either the mother or daughter was driving. After he examines the steering wheel column, Walter finds a fiber. He explains that the plastic momentarily cracked, trapped the fiber, then reformed. Calleigh determines the fiber matches Lily's pants and her as the driver.

After she wakes up, Lily tells Horatio and her dad that she drove because Karen didn't have her glasses and Greg had his license suspended. She says her mom was next to her and Greg was in the back. Lily says she saw a gator in the road, swerved and hit the luxury car. She says the car felt heavy. She says what happened is all her fault.

Horatio and Ryan examine the car. They see that the steering fluid is very low. Ryan finds that steering fluid hose was cut. They figure someone intentionally tried to kill Karen. Horatio brings in Ballard and tells him he had access and motive. Tripp informs Ballard that his wife had a boyfriend. Horatio figures the fact upset him. Ballard says he didn't think his kids would be in the car. Ballard admits he was not in his office and was watching a football game. Ballard says he would never hurt Karen, but Horatio informs him he is still their lead suspect.

The team brings in the tools from Ballard's garage. Calleigh announces her doubts that Ballard wanted to kill his family. They smell marijuana in the air. The team sees that the source is coming from under the hood. Jesse digs in the car and finds a bag. They figure that the person who hid it accidentally cut the line. Ryan remembers that Greg was caught smoking weed. Later, Greg admits that he scored drugs and hid the bag under the hood. Horatio informs Greg that he inadvertently cut the steering fluid cable. Greg realizes he is the cause of his mom's death. He says he didn't think his drug use could cause such problems. Greg instructs the detectives to tell Lily it was not her fault.

Marta learns that Jesse and the detectives had her ex drop the charges. Marta blames herself for her brother's death, but Jesse assures her it wasn't her fault. He says Victor was a hero when he pulled the kid from the wreck.