Insurance group pushes to keep kids in protective seats longer.
California is the latest state to require that children in cars ride in a booster seat until they're 8 years old.
The new law takes effect in January and will raise the current requirement that they ride in them until age 6.
California joins 31 other states in wanting kids to stay in booster seats longer, which researchers say has already produced dramatic results.
"In these states, the risk of serious injury and fatality in a crash went down by 17%," Explains Anne McCartt of the Insurance Institute for Highway Safety.
The Insurance Institute is pushing the other 19 states, and points to its latest crash test results that boosters work when the shoulder and lap belts are properly positioned.
"It's not riding up on the abdomen, which is vulnerable to injury in a crash. The shoulder belt is fitting snugly across the center of the shoulder, you don't want it riding off the shoulder or riding up on the neck," McCartt says.
The Institute released results this morning of crash tests involving 62 models of booster seats, with half getting a good rating and many available at affordable prices.
Boosters are for children too big for car seats, but not quite big enough for only adult restraints.
You can check out how specific boosters fared at the institute's website: iihs.org