SAN FRANCISCO -- If you have an unpaid traffic ticket that's been gathering dust for three years or more, the state has a deal for you: Pay up during the first six months of 2012, and get 50 percent off.

The one-time discount, authorized by a new state law, is designed to help both delinquent drivers and financially strapped state and local governments.

The Administrative Office of the Courts expects the program to generate $46 million, based on a conservative estimate that 2 percent of the overdue fines will be collected, said Jessica Sanora, manager of the office's Enhanced Collections Unit. That means the current statewide tab is more than $900 million.

"We believe it's due a lot to the economy. Because of the high fines, people are just unable to pay," Sanora said.

The revenue will be divided among the state, cities, counties and courts.

The discounts apply to fines that were due before the start of 2009 for any traffic violation except drunken or reckless driving. They do not cover parking tickets.

Sanora said counties will have the option of limiting the discounts to traffic infractions, like running a red light or speeding, and excluding more serious violations punishable as misdemeanors, like driving with a suspended license.

Traffic tickets are expensive in California because of a plethora of fees and surcharges added by the state and the counties over the years. The biggest is a civil assessment of up to $300 for drivers who fail to pay their fine when it is due or fail to show up in court. That money goes to a statewide fund to support Superior Court operations.

Drivers with unpaid tickets are subject to the government's usual debt-collection practices, including confiscation of state tax refunds.

California offered similar discounts in 1992 and 1996, Sanora said. She said the state collected $15.5 million in 1992 and has no figures available for 1996.