By Mike Sacks 

WASHINGTON — The U.S. Chamber of Commerce is undefeated at the Supreme Court this term, continuing to improve its success in securing business-friendly judgments since Chief Justice John Roberts took the bench in 2005.

The Constitutional Accountability Center, a left-leaning think tank and law firm, reported its findings on Thursday, noting that this term, which began in October and will likely conclude by the end of June, could be the chamber’s “first ‘perfect’ term before the Supreme Court since at least 1994.”

This term’s “string of seven straight victories brings the chamber’s overall win/loss rate before the Roberts Court up to 68 percent (60 of 88 cases),” wrote Neal Weare, the center’s litigation counsel and Supreme Court fellow. That success rate is significantly higher than during comparable periods of personnel stability under the past two chief justices, William Rehnquist and Warren Burger. From 1994 to 2005, when Rehnquist was chief justice, the chamber succeeded in 56 percent of the cases it backed. The business lobby had a 43 percent success rate from 1981 to 1986 during the final years of Chief Justice Warren Burger’s tenure.

The chamber, a pro-business lobbying group that supports conservative candidates and causes, formed its modern litigation strategy in 1971, when corporate attorney Lewis Powell wrote a memorandum that urged the group to aggressively pursue its interests in courts, citing the liberal American Civil Liberties Union’s success as a model. “Under our constitutional system, especially with an activist-minded Supreme Court, the judiciary may be the most important instrument for social, economic and political change,” Powell wrote. Then-President Richard Nixon nominated Powell that same year to the Supreme Court, where he wrote the opinion that the Roberts Court relied upon in the Citizens United decision to allow unlimited corporate spending in political campaigns.

The health care cases, likely to be decided next week, may yet spoil the chamber’s perfect season. The chamber took no position on the individual mandate’s constitutionality, but did urge the justices to strike down the entire law if they decide to void the mandate. That position, however, found little support among the justices during oral argument in March.

Still, not even a loss in the Supreme Court’s highest profile case of the term, if not the decade, would do much to dent the chamber’s high rate of success at the Roberts Court.

CORRECTION: 11:35 p.m. — This article has been updated to show that the Constitutional Accountability Center study of the Rehnquist and [Burger] courts did not count all of the U.S. Chamber of Commerce cases in all of the years of those courts. The center study was designed to compare periods of court personnel stability.