Charleston Mayor Joe Riley is coming under attack from an anonymous political group that can keep its fundraising and contributors secret because of a federal court ruling last fall.

A group called "Citizens for a Better Charleston" distributed fliers Monday promoting Charleston City Councilman Dudley Gregorie as a "Reagan Conservative" and bashing Riley.

Also, new websites -- www.thejoerileyfile.com and www.abettercharleston.org -- appear to be part of the effort to discredit Riley as he seeks a 10th term.

The twist is that no one knows who is paying for it all -- and that its backers are immune to the $3,500 limit that applies to donations to candidates, said Capers Barr, Riley's campaign manager.

"This is just a supreme act of political cowardice," Barr said. "It's like throwing rocks from behind the schoolhouse and hiding behind it."

Gregorie, who appears to be benefiting from it, said Monday he has no knowledge of the group.

"I've heard (things), but I don't know anything about them. I haven't seen anything that they've done yet," Gregorie said. "It's tough to comment on something you haven't seen."

Political action committees and other third-party groups were required to abide by the state's limits on campaign donations -- and to report their donors and expenses to the State Ethics Commission.

However, that law essentially disappeared in September 2010, when a U.S. district judge in Florence ruled that the state's definition of committee was too vague, said Cathy Hazelwood, general counsel for the State Ethics Commission. The suit was

S.C. Citizens for Life vs. (State Ethics Commission Chairman) Kenneth Krawcheck.

"There are no rules, regulations, contribution limits, etc. for noncandidate committees or PACs (political action committees)," she said. "Candidates still have all the filing requirements. They still have contribution limits, disclosure, etc., but there are no rules for PACs."

Attempts to contact Citizens for a Better Charleston on Monday were unsuccessful. The group's address is a post office box on Market Street.

Hazelwood said the commission notified state lawmakers about the ruling last year so they could consider amending the definition to provide transparency for such groups. The Senate introduced a bill late in the session, but it didn't pass.

Hazelwood said most of the 162 PACs that previously filed reports are continuing to do so, but she receives about one complaint a week regarding other groups who have not disclosed their donors.

"On a regular basis, I take a call saying, 'Here's a group doing this. Why can't I find them in the system?" she said.

Riley could not be reached for comment late Monday but is likely to hold a press conference about the donations today, Barr said.

"We're going to win this election," Barr said. "But what an effort like this does is it attacks the ability of a positive and affirmative leader to affirmatively lead his community. That's what they're trying to do. They're trying to undermine that."

School teacher Craig Jelks, author David Farrow and restaurant manager Joshua Kennedy also are running for mayor.

The city's election is set for Nov. 8.

Reach Robert Behre at 937-5771.