The city Board of Ethics for the first time in nearly 60 years is reconsidering whether City Council's 180-some staff members should continue to be exempt from restrictions on political activity by city workers.

The restrictions are based on the city's Home Rule Charter, approved by voters in 1951.

The charter prohibits the city's appointed officers and employees from running for public office, soliciting political contributions or taking "any part in the management or affairs of any political party or in any political campaign, except to exercise his right as a citizen privately to express his opinion and to cast his vote."

A civil-service rule known as Regulation 29 - so old that current city officials are unsure when it was adopted - is now in place to tell city workers what they can and cannot do.

They're allowed to join political parties and nonpartisan civic groups, to vote in any election and express private opinions about candidates and political issues.

But the regulation prohibits city employees from wearing campaign buttons or distributing fliers. They're barred from writing or publishing any letter or article that endorses or opposes any candidate or party.

The Board of Ethics - an independent panel of five people, nominated by the mayor and confirmed by Council - hopes to adopt a new political-activity regulation by the end of the year.

A preliminary draft, developed by the board's staff, was distributed this week to about 45 city officials, civic groups, reporters and others.

It's generally consistent with the existing civil-service regulation, prohibiting any political activity while employees are on duty, in uniform or at their workplaces.

It would ease restrictions slightly, by allowing off-duty employees to wear campaign buttons, plant candidate signs on their front lawns or endorse candidates in Internet postings or letters, as long as the communication does not identify the writer as a city employee.

But the biggest potential for controversy is an issue that the draft report does not address - whether political-activity restrictions should be extended to employees of Council, exempted in 1952 from the city charter restraints by then-city solicitor Abraham Freedman.

Mayor Nutter's city solicitor, Shelley R. Smith, advised the Board of Ethics two years ago that on ethical issues the board is not bound by past opinions of the city Law Department.

That gives it the authority to apply the new political-activity limits to Council's staff. As alternatives, it could continue their exemption, or carve out a compromise that would put Council employees under some restrictions, but not others.

Six of the 17 elected Council members are also Democratic ward leaders. Council staff includes at least four ward leaders and a number of Democratic and Republican committeemen. Many owe their jobs to a Council member or other political connection.

"I don't think there's been any problem with it," said Councilman Bill Greenlee, also the Democratic ward leader in Fairmount.

Greenlee spent 26 years working as a Council staff member, mostly as an aide to the late Councilman David Cohen, before winning election himself after Cohen's death in 2005. He said he couldn't remember ever seeing a Council employee do political work on city time.

"I think people should be allowed to engage in political activity, if they see fit, on their own time and away from the job," Greenlee said. "As a committeeman and a ward leader, I was out in the community, and I think it helped me do my job better because I knew what was going on."

But government-reform organizations, including the Committee of Seventy and last year's Task Force on Ethics and Campaign Finance Reform, have both opposed the Council exemption.