Washington's traditional July 4th fireworks display is getting an early start this year -- in court.

The pyrotechnics begin tomorrow morning before U.S. District Judge Joyce Hens Green when Zambelli Internationale Fireworks Manufacturing Co., which has produced most Mall extravaganzas during the past three decades, takes on the National Park Service for awarding the contract for Friday's show to a newcomer, Vitale Fireworks Co.

The fireworks usually attract hundreds of thousands of persons to the Mall and serve as the traditional climax to the daylong festivities.

The legal issues center on whether Vitale, Zambelli's cross-town rival in New Castle, Pa., met the contract's requirement to provide $1 million liability insurance coverage.

According to Zambelli's lawsuit, filed last Friday, Vitale was awarded the fireworks display contract even though its bid, at $40,000, was $5,000 more than Zambelli's and even though Vitale's insurance is to be provided by a firm not licensed to do business in the District.

National Park Service spokeswoman Sandra Alley said that because the matter is in litigation the Park Service will not comment.

Christopher Kerns, Zambelli's lawyer, said yesterday that the issue is a matter of prestige.

Zambelli, a century-old family operation, is scheduled to light up the skies Friday night in more than a thousand locations. It is one of three firms that will produce the "International Fireworks Spectacular" for the Statue of Liberty centennial celebration.

"The Mall fireworks display is very prestigious," Kerns said, and, despite other commitments, Zambelli always sends its "best team" here. George Zambelli, the firm's head and grandson of the Neapolitan immigrant who founded the company, usually has headed the production crew in the past.

Zambelli has asked Green to block Vitale from carrying out the contract and to determine which bidder should have been chosen.

"We believe that Vitale will try to delay this past Monday," Kerns said, adding that another firm would need at least three days to assemble and install the equipment needed for the 30-minute show.

Kerns said that because of the lack of liability insurance, the D.C. Fire Department has refused to issue a permit for the fireworks display. This will not necessarily stop the show, since the District does not have the authority to force a federal agency to comply with city laws.

"But the Park Service wouldn't just be taking the risk for its own sake, it would be taking the risk for the public and the . . . D.C. firefighters and police officers who will be standing by," Kerns said.

Telephone calls to Vitale were not returned yesterday.