By David Porter, AP

NEWARK, N.J. — A federal judge upheld a 21-year-old law prohibiting sports betting in all but four states, dealing a setback to New Jersey’s attempts to revive its struggling casino industry by grabbing a piece of what has become a multibillion-dollar industry, both legal and illegal.

The ruling published late Thursday night marked the second defeat for New Jersey in a lawsuit filed last year by the four major professional sports leagues and the NCAA. In a December ruling, U.S. District Judge Michael Shipp denied the state’s claim that the leagues and the NCAA didn’t have standing to bring the suit because they couldn’t demonstrate tangible harm to their products if New Jersey were to allow sports betting.

“We believe firmly in the principles of our position on sports betting and that the federal ban is inequitable, violates New Jersey’s rights as a state and is unconstitutional,” Gov. Chris Christie said.

State Sen. Ray Lesniak, the prime sponsor of the sports betting bill, said New Jersey would appeal Shipp’s “patent misinterpretation of the Constitution.”

This week, Christie signed a bill making the state the third in the nation to allow gambling over the Internet. New Jersey’s casino industry has seen revenues decline steadily over the last several years in the face of competition from neighboring states. Atlantic City’s newest casino, Revel, announced last week that it will file for Chapter 11 bankruptcy protection next month, about a year after it opened.

New Jersey voters passed a sports betting referendum in 2011, and last year the Legislature enacted a sports betting law that limited bets to the Atlantic City casinos and the state’s horse racing tracks. Bets wouldn’t be taken on games involving New Jersey colleges or college games played in the state.

The NFL, NHL, NBA, Major League Baseball and the NCAA sued the state last year, and the NCAA has moved several of its championship events out of New Jersey because of the sports betting law.

New Jersey, represented by former U.S. Solicitor General Theodore Olson, among others, had attacked the 1992 Professional and Amateur Sports Protection Act, or PASPA, on several constitutional levels. In filings, the state argued the law unfairly “grandfathered” Nevada, Oregon, Montana and Delaware, which already have some form of sports gambling.

On Thursday, Shipp said that although some of the questions raised in the case were novel, “judicial intervention is generally unwarranted no matter how unwise a court considers a policy decision of the legislative branch. As such, to the extent the people of New Jersey disagree with PASPA, their remedy is not through passage of a state law or through the judiciary, but through the repeal or amendment of PASPA in Congress.”