Gov. Jerry Brown has vetoed a bill that would have required middle and high schools to start their classes no earlier than 8:30 a.m.

The measure, SB 328 by Sen. Anthony Portantino (D-La Cañada Flintridge), sparked impassioned debate in the Legislature that did not break down upon party lines.

Supporters pointed to research from the American Academy of Pediatrics and others showing that students are more awake and learn better when school starts later.

Opponents said the state should not interfere with local control.

About 80 percent of California schools begin classes earlier than 8:30 a.m., according to research from the U.S. Department of Education and a legislative analysis of the measure.

In his veto message, the governor called the measure a “one-size-fits-all approach” that is “best handled in the local community.”

His rejection is not a surprise. Brown has long spoken of what he calls the “principle of subsidiarity” — delegating decision-making powers to local school districts whenever possible.

Despite the science supporting later start times, the bill was opposed by both teachers’ unions and school boards.