The city's Board of Ethics has fined the Carpenters Union $1,000 for donating $21,500 - $10,000 over the limit - to State Sen. Anthony Hardy Williams' mayoral campaign, and the union has agreed to pay.

Whether Williams' campaign will have to return the extra $10,000 was not clear Thursday.

Asked about the $10,000, Al Butler, Williams' campaign spokesman, wrote in an e-mail, "We are aware of the issue and working with the Ethics Board to resolve it as soon as possible."

The Ethics Board said Thursday that it had reached a settlement with the Carpenters PAC of Philadelphia and Vicinity, the political arm of the city-based Metropolitan Regional Council of Carpenters, but there was no mention of a penalty for Williams.

The PAC gave $10,000 to Williams' senatorial campaign committee in January 2014 and 10 months later gave $11,500 - the maximum a PAC can give to a single candidate in a single year - to Williams' mayoral campaign.

According the campaign finance regulations, if a candidate or his or her political committee accepts a contribution in excess of the limits, it is subject to a civil penalty of "three times the amount by which the accepted contribution exceeded the limit, or $2,000, whichever is less."

The same rule applies for the contributor who made the excess donation.

"The Carpenters PAC immediately acknowledged the violation and agreed to resolve the matter by settlement," according to the settlement, signed by PAC chairman Ed Twiford.

The only penalty listed in the agreement is the $1,000 fee to be paid by the PAC. Officials at the Ethics Board declined to comment on whether Williams will have to pay back the money.