The L.A. Times is reporting:

The legal battle over gay marriage will heat up again today, when the first briefs in the lawsuit over the validity of Proposition 8 are due to the California Supreme Court.

Proposition 8, which amended the California Constitution to ban same-sex marriage, was approved by 52% of California voters last month, throwing into question thousands of marriages performed during the five months the practice was legal in the state.

The day after the election, gay-rights advocates, including the cities of San Francisco and Los Angeles, filed lawsuits to invalidate the proposition.