By BOB EGELKO, San Francisco Chronicle

One of the most momentous and least-discussed topics in the presidential campaign is the likely departure in the next four years of as many as three of the more liberal justices on a closely divided U.S. Supreme Court.

WASHINGTON -- A proposed Bush administration regulation on contraception and abortion would stop California from enforcing a state law that requires Catholic hospitals and charities to provide birth control coverage for thousands of female employees, state Attorney General Jerry Brown and family-planning advocates say.

A California appeals court upheld the state's 12-year-old medical marijuana law this week, rejecting two counties' arguments that allowing patients to use the drug with their doctor's approval condones violations of federal narcotics laws.

Backers of a November initiative to ban same-sex marriage in California plan to tell voters in the state ballot pamphlet that the constitutional amendment would protect children as young as kindergarten age from being taught in school about the virtues of gay and lesbian matrimony.

SAN FRANCISCO -- Brewster Kahle, who runs an online library in San Francisco, was appalled when his volunteer lawyers told him in November that the FBI was demanding records of all communications with one of his patrons as part of an investigation of "international terrorism or clandestine intelligence activities."

The legal battle over same-sex marriage in California is also a clash of religions.

SAN FRANCISCO -- An Arizona anti-abortion group's right of free speech was violated when the state refused to issue specialty license plates with the message "Choose Life," a federal appeals court ruled this week.

The Nevada Supreme Court's ruling allowing a cable network to exclude Dennis Kucinich from a Democratic presidential debate was barely a blip on the media radar screen, quickly forgotten in the reporting of the caucus victories by Hillary Rodham Clinton and Republican Mitt Romney and the squabble over voting in casinos.