A final attempt by Sempra Energy to stop a $24 billion antitrust class action lawsuit from going to trial has failed, following the denial of a writ of mandate last week by the 4th District Court of Appeal in San Diego, the plaintiffs’ attorneys said today.

Sempra will face a jury next year relating to charges of conspiracy and market manipulation that gave rise to California’s energy crisis of 2000 and 2001. The civil action seeks damages of nearly $24 billion.

The suit claims Sempra and two subsidiaries, Southern California Gas Co. and San Diego Gas & Electric, conspired with El Paso Natural Gas Corp. to prevent competition for cheaper Canadian natural gas and to protect their market dominance over the supply and transportation of natural gas into and within California, reaping enormous profits.

Plaintiffs in the class action include the state of California; the city and county of Los Angeles; San Bernardino County; Long Beach, Burbank, Glendale, Culver City, Vernon and Upland; Continental Forge Co.; and numerous other companies and individuals. The case also includes a class of more than 13 million California consumers who paid inflated gas and electric bills.

The trial date, anticipated for next summer, is expected to be set early next month.