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He was on the hood of a car and slammed his head on the pavement when the driver stepped on the brakes.
"His cousin, who is a minor, jumped out and on the hood of the car. He hit the brakes and the juvenile fell off the car and struck his head. He was transported to a local hospital in Northridge. He is in critical but stable condition as of this minute," said Sgt. Bill Justice, LAPD Valley Traffic Div.
It appears he might have been hoodsurfing. As the name implies, it's riding the hood of a car, sometimes at high speeds.
It's been glorified on YouTube by people sending in their home videos.
"When they use a motor vehicle they put the entire community at risk. And here we have a young individual who was engaging in this activity with another young individual and it resulted in very serious injuries to this person," said Capt. Ronald E. Marbrey, LAPD.
All of this is against the law. The vehicle code is quite clear: You can't ride on a vehicle or on any part of a vehicle that's not intended for passengers.
In this case not only is one person in critical condition, the driver was allegedly drunk.
"The driver turned out to be under the influence of alcohol and was subsequently booked for driving under the influence. And because someone was hurt in the accident it makes it a felony," said Sgt. Justice.
"This is a prime example of why it is illegal. People can get hurt. We are asking folks not to drive outside the vehicle. People shouldn't be hanging out the windows, you can't be on the hood of the car, you can't be towed by skateboards. You cannot do these kinds of things because this is the result," said Capt. Marbrey.