CHICAGO—Just a single incident of sexual harassment, if severe enough, can violate federal civil rights law, says a federal appellate court in a decision Monday.

The decision by the Chicago-based 7th U.S. Circuit Court of Appeals in Cynthia Berry vs. Chicago Transit Authority involved a dispute by Ms. Berry, who was a carpenter with the CTA, with a fellow worker over a card game in January 2006.

Ms. Berry said after she refused to get up so that a co-worker, Philip Carmichael, could partner with another worker in a game during a morning break, Mr. Carmichael grabbed her breasts, lifted her up from a bench and rubbed her buttocks against the front of his body. Ms. Berry said that when she landed off-balance with only one leg on the ground, Mr. Carmichael pushed her into a fence.

When Ms. Berry reported the incident to a manager, he told her he did not care what happened because she was a “pain in the butt,” predicted she would lose her job if she filed charges, and promised he was going to do “whatever it takes to protect the CTA,” said the opinion.

Ms. Berry filed suit against the CTA in July 2006, claiming Mr. Carmichael's actions and the manager's response created a hostile work environment and constituted sex discrimination in violation of Title VII of the Civil Rights Act of 1964. A district court subsequently granted the CTA's motion for summary judgment dismissing the case.

The appellate court said with respect to Mr. Carmichael's actions, “Berry has provided enough evidence to allow her hostile work environment claim to go forward. As the district court noted, a single act can create a hostile environment if it is severe enough.”

The court also said Ms. Berry's testimony “would allow a reasonable fact finder to conclude” that the manager “maliciously thwarted any legitimate investigation and that the CTA was therefore negligent or worse in responding to her report of harassment.”

The three-judge panel, however, upheld the lower court's dismissal of Ms. Berry's discrimination and retaliation claims. The case was remanded for further proceedings.

Plaintiff attorney Paul Mollica, a partner with law firm Meites, Mulder, Mollica & Glink in Chicago, said although the civil rights law establishes that a severe-enough single incident of harassment violates the law, most lawsuits charge either pervasive, or severe and pervasive, harassment. “There aren't a lot of cases like this where a solitary act is evaluated,” he said.