A federal judge certified all of the victims of the Indiana State Fair concert stage collapse into a single class Wednesday in a lawsuit challenging a law that caps the state's liability at $5 million, but she concluded the plaintiffs are unlikely to win the challenge.

The ruling by U.S. District Judge Sarah Evans Barker in Indianapolis allows the estates of three of the seven people killed in the Aug. 13 collapse to pursue their federal constitutional challenge to Indiana's tort claim law, which caps the state's financial liability at $700,000 per victim and a total of $5 million for all victims.

Besides the seven people killed in the collapse before a concert by the country duo Sugarland, more than 40 other victims also suffered physical injuries, and many more claim they were hurt in other ways.

Barker denied the plaintiffs' request for a preliminary injunction that would prevent any payouts from the $5 million fund to victims of the collapse, saying they had not shown they are likely to win the case, a required step before federal preliminary injunctions are granted.

"We cannot conclude that ... plaintiffs are clearly 'likely' to succeed on their assertion that Indiana's tort claims damages caps violate the federal Constitution," Barker wrote in a 26-page ruling.

However, plaintiffs' attorney Kenneth J. Allen of Valparaiso saw the ruling as a clear victory in his clients' bid to get the Indiana tort claims law thrown out. Instead of Indiana-employed judges deciding the constitutionality of the law, it will be federal judges, he said.

"Challenging the tort claim limits in federal court gives us a great opportunity for fair and impartial review not colored by the fact that the state treasury is involved or that state employees need to decide whether the state needs to pay more money," Allen said in a telephone interview.

He predicted the lawsuit citing the 14th Amendment protections to due process and equal protection eventually would go before the U.S. Supreme Court and that the Indiana law would receive the scrutiny it deserves.

"We think ultimately, if the U.S. Supreme Court looks at it in a rational light, it will be overturned," Allen said.

Indiana Attorney General Greg Zoeller, named as a defendant in the lawsuit with Gov. Mitch Daniels, said his office was working with about 30 law firms, a mediator, and victim compensation expert Kenneth Feinberg to split up the $5 million "fairly and equitably, and we hope to conclude the settlement process soon."

"We still are reviewing the Court's ruling, but it allows the State to continue negotiations with more than 100 claimants who applied for expedited settlement payments from the state's Tort Claim Fund," Zoeller said in a statement.

Allen represents the estates of Tammy Jean VanDam of Wanatah, Christina Santiago of Chicago, and Alina Bigjohny of Fort Wayne, and three other women who survived when the stage and some of its rigging collapsed after a wind gust of at least 60 mph that swept through the state fairgrounds on Indianapolis' north side.

A separate lawsuit filed Tuesday in Marion Superior Court in Indianapolis on behalf of the estates of the four other people who died and 44 other victims seeks unspecified damages from Sugarland, producers, stage riggers and others associated with the concert.