Any eligible 16- or 17-year-old who gets a California driver's license or state ID card at the DMV will automatically become pre-registered to vote under a measure signed into law by Gov. Jerry Brown.

Qualified teenagers of that age who are pre-registered will then be ready to vote when they turn 18 without additional paperwork. Although the law takes effect January 2019, officials plan to roll out the program in April along with an upcoming change at the DMV for voters of all ages.

Currently, the DMV has an opt-in process to register to vote. But starting in April, people 18 and older will be automatically registered to vote unless they opt out. Pre-registration for those who are 16 and 17 will be implemented at the same time.

The new law is expected to boost voter registration numbers by about 200,000 young citizens per year, according to Assembly member Kevin McCarty's office. The Democrat authored the law along with Assembly member Lorena Gonzalez Fletcher.

“It’d be the largest voter registration expansion that we’re aware of in our nation’s history," said Terry Schanz, McCarty's chief of staff.

The teenagers can choose not to be pre-registered, but they must specifically opt out of the system. When first pre-registered, they will be automatically listed as having no party preference and can choose a party later if they choose.

California first put pre-registration for 16- and 17-year-olds into effect in November 2016 but it currently requires action by the teenagers themselves to sign up.

This story has been updated with additional information on the implementation date of the pre-registration system for 16- and 17-year-olds.