A Salt Lake City civil-rights attorney plans to sue over a city ordinance enacted this week that restricts neighborhood protests, and Mayor Rocky Anderson concedes the rule needs some reworking.

Attorney Brian Barnard said Friday that he will file a lawsuit, probably on Monday, on behalf of the Anti-Hunger Action Committee, seeking to change the ordinance that bans picketing and other demonstrations within 100 feet of a residence when the protests are targeted at an individual living there.

Barnard said his lawsuit will be on First Amendment grounds as AHAC members worry the ordinance stifles their freedom of speech and prevents them from rallying in front of the Governor's Mansion.

The ordinance passed the City Council on a 5-2 vote Tuesday in response to a request from University of Utah researchers whose homes have been targeted by protesters from the Utah Primate Freedom Project, a group opposed to animal research.

It passed without a public hearing — a legally permissible move but one that opponents have criticized as being unusual for the council, which usually hears a briefing from city staff on proposed ordinances and then waits for at least a week before voting on them.

Anderson's administration backed the ordinance, but the mayor said Friday there is probably good reason for amendments to fix its unintended consequences.

"It may need some tweaking over time," Anderson said. "If it includes, for instance, publicly owned residences like the Governor's Mansion, maybe there should be some changes. I frankly didn't realize that would be included."

Barnard said he was glad to hear the mayor is willing to consider changes to the ordinance. Barnard criticized what he sees as a rush job by the council and said he hopes the city will put a hold on enforcing the ordinance until it is amended.

"It's a step in the right direction," he said of the mayor's comments. "That's the kind of thing that should have been thought about before the ordinance was passed."

Anderson, himself a former civil-rights attorney who participated in a 1992 capital punishment protest at the mansion, believes the new picketing ordinance can achieve a balance.

The goal, he said, is to "protect private citizens and their neighbors from fairly outrageous infringements on peace in their neighborhoods. Because somebody works at a lab shouldn't mean that people are in their neighborhoods with bullhorns, not only disturbing them if they happen to be home but also their neighbors. There are other ways to express opinions than to harass people."