Washington ? A federal appeals court on Tuesday struck down a government fine against AT&T Corp., which had been accused of switching consumers’ long-distance service without permission.

The U.S. Court of Appeals for the District of Columbia ruled that the Federal Communications Commission overstepped its authority when it fined AT&T $80,000 for two cases of “slamming,” the illegal practice of switching telephone service providers without consent.

In December 2000, the FCC fined AT&T $520,000 for 11 violations of federal slamming rules, the court said. The company paid the fine, but contested two incidents where consumers complained that they didn’t know who had authorized a change of their phone service.

The appeals court agreed with AT&T’s position that the company had done enough to verify the identities of the long-distance subscribers before switching service.

“AT&T has a zero-tolerance policy for slamming and in this particular case we followed the FCC’s authorization rules to the letter,” said AT&T spokeswoman Claudia Jones. “The FCC tried to hold us liable even though we did nothing wrong.”

An FCC spokesman said the agency was reviewing the court decision and had no immediate comment.

It was unclear how the ruling would affect other FCC fines for slamming.