In the second legal challenge in a little more than a month to a piece of Pittsburgh City Council legislation, a trade association and a group of local businesses are suing the city over its paid-sick leave ordinance, signed into law by the mayor in August.

The Pennsylvania Restaurant and Lodging Association joined Storms Restaurant and Catering, The Church Brew Works, Rita’s Italian Ice, Dirt Doctors Cleaning Service and Modern Cafe, Inc. in a suit filed Monday that called the law, which requires all businesses in the city to provide paid sick leave, “an illegal exercise of municipal authority.”

Barney Oursler, executive director of Pittsburgh United, a coalition of unions, community organizations and advocacy groups that pushed council to pass the measure, said the ordinance means “50,000 Pittsburghers won’t have to choose between staying home sick and losing a day’s pay.”

“Thousands of Pittsburghers, over 25 organizations and public health researchers stood with City Council to say that paid sick days are critical to the public health and it’s not right for corporate lobbyists from Harrisburg to tell us how to run our city,” he said.