While the gay and lesbian community is celebrating the Supreme Court ruling that struck down California's Defense of Marriage Act, another group can also be happy about high court decisions this term—the U.S. Chamber of Commerce.
According to the Constitutional Accountability Center (CAC), the chamber has a 78 percent success rate in recent Supreme Court decisions, finding itself on the winning side in 14 out of 17 cases in which it filed amicus briefs.
An amicus brief is a court document filed by a party not directly related to a case, but which is used to influence the court's decision.
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"We've studied this the past few years and the chamber is more successful now than in previous terms," said Judith Schaeffer, vice president of the CAC, a think tank and law firm.
Since 2006, the chamber has won 70 percent of its cases, compared with 56 percent during a comparable period when William Rehnquist was chief justice from 1985 to 2005, said the CAC.
"The court doesn't hold for business in every case, but it's a conservative court and more often than not, they agree with the chamber," Schaeffer said. "And when you have these cases closely divided and along a 5-4 vote, the chamber almost always wins."
The Chamber of Commerce, which represents the interests of more than 3 million American businesses, chose not to comment for this story after being contacted by CNBC.
In fact, according to the CAC, of the eight 5-4 recent decisions on business-related cases, the chamber was on the winning side in all eight. (Justices Scalia, Kennedy, Thomas, Alito and Chief Justice Roberts have been the majority, while justices Ginsburg, Sotomayor, Breyer and Kagan have been the minority.)
Among the key decisions this month with chamber amicus briefs were rulings making it harder for people to sue businesses for retaliation and discrimination.
In one case, the court said—in a 5-4 vote—that a person must be able to hire and fire someone in order to be considered a supervisor, thereby making it more difficult for a plaintiff to blame a business for alleged sexism or racism from a co-worker who isn't a manager.
That case was Vance v. Ball State University, where a female worker sued her supervisor and employer Ball State University for racial harassment and retaliation. The court ruled that the supervisor was really a co-worker and could not hire or fire the plaintiff, and that Ball State was not liable.
In University of Texas Southwestern Medical Center v. Nassar—also a 5-4 decision—the court agreed with a lower court ruling that restricted when juries can rule that businesses have retaliated against employees.
Retailers Lose to AmEx
Perhaps one of the biggest decisions that went the chamber's way was the Supreme Court's ruling this month on arbitration.
The legality of that practice was given support by the court when it ruled in favor of an arbitration agreement that prevents merchants from banding together to make antitrust claims against American Express in American Express v. Italian Colors Restaurant.
"What it means is that if you have a dispute, you can't go to court," Schaeffer argued. "You have to use an arbitrator where [unlike in a courtroom] the rules of evidence don't apply, and you end up having to pay for the arbitrator anyway."
"That decision really hurts consumers," said Schaeffer. "We buy cellphones and other products, and each one of those contracts has an arbitration clause buried someplace in [the] fine print."
However, some analysts see no political agenda behind the court's decisions this year.
"The chamber has to be happy of course with these rulings, but I don't think the court is doing anything but looking at the law," said Amy Gordon, an employment benefits lawyer at McDermott Will & Emery.
"Don't forget, they ruled in favor of Obamacare with Chief Justice Roberts in the majority 5-4 decision," Gordon said. "So while this is a more conservative and business-friendly court, I don't think there's a political agenda here."
Gordon added that if there were some outside influences on the court, they would more likely be the state of the economy.
"it's not the first level of importance for them, but I do think it weighs on their decisions," Gordon said. "The court could be looking at things from the employer perspective and realizing how difficult it is to do business with a pro-labor administration."
"They could be thinking of how to get people back to work," Gordon said.
Keeping the Streak Alive
As for what the chamber will do in the future, experts expect more of the same.
"The chamber has been filing for years in these types of cases but the fact they've been successful may be fueling their efforts," said Gordon. "And since they have been on the winning side, it only adds more weight to their opinions."
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"There's no denying the chamber impact on these cases," said Schaeffer. "And it's likely to continue."
—By CNBC's Mark Koba.