As Philadelphia closes out a difficult year, a proposed sweeping reform of the city's property-tax assessment system is one of the most promising developments in decades.

Thanks to action by City Council, voters next May will be asked to abolish the infamous Board of Revision of Taxes. It's a major step toward establishing fairness and competence in the setting of property values citywide.

Voters should approve this measure, which will allow a change to the City Charter. The BRT would cease to exist on Sept. 30 next year, and would be replaced with an Office of Property Assessment under the indirect control of Mayor Nutter. A separate board would hear appeals from property owners.

The goal is a transparent, uniform property-tax system free from the political deal-making that has resulted in so many inequities in the past. What a concept.

None of these reforms would be taking place without an eye-opening series of articles in The Inquirer, which detailed the many failures of the BRT. For decades, the agency has been a patronage-laden jobs bank for cronies of the powerful, cutting deals for influential property owners and setting other property values with little rhyme or reason.

The BRT flouted Sunshine laws, operating in secrecy and controlling a system of assessments that is one of the least equitable in the nation. It results in many property owners paying too much in taxes, while others with political connections pay too little.

To their credit, Nutter and Council moved to change this faulty system. Other elected leaders over the past half-century or more were content to simply exploit the spoils of this hack shop.

Council President Anna C. Verna said the ballot measure is only a first step, and she's right.

As she and others who've played the patronage game should know, setting up a professional system to replace the BRT largely depends on the commitment of public officials not to meddle with the new agency. Its fairness and accuracy will depend on independence from political chicanery.

Nutter made a good start on that front by appointing Richard Negrin, an attorney at Aramark, as the BRT's interim executive director. He has a reputation for integrity and independence.

More will need to be done to trim the agency's patronage-laden staff of political operatives who double as BRT clerks.

But the best news to date is that voters next May will be presented with this ballot question: "Shall the Board of Revision of Taxes be abolished, and its powers, functions, and duties be reassigned to a new Office of Property Assessment (with respect to the making of assessments) and to a Board of Property Assessment Appeals (with respect to appeals from such assessments), with the members of the board appointed from nominations made by a Board of Property Assessment Appeals nominating panel?"

The answer is yes, a thousand times yes.