"It reduces the clear lines of accountability," said Mark McDonald, spokesman for Mayor Nutter.
"We believe it would slow down the contracting process, would add unnecessary costs and, we thought, most importantly, it would dilute the authority in city government for the management of city affairs."
In October, Councilman Dennis O'Brien, the primary sponsor of the bill that put the question on the ballot, fought the administration on hiring a private law firm to represent indigent clients when the city's public defender had to abstain. O'Brien claims he was worried a private practice would put profits before clients.
"I do not believe that every contract should require City Council approval. However, I do strongly believe that any contract dealing with an individual's constitutional rights is important enough to require Council approval," he said.
"I understand that amending the Home Rule Charter is not an action to be taken lightly, but these contracts are of such importance that an exception to the charter is not only required, but in the best interest of the city."
Also Tuesday, voters approved a ballot measure dictating that city subcontractors must pay workers 150 percent of the federal minimum wage, or $10.88 an hour.
But voters rejected a "resign-to-run" measure, that would have let politicians keep their current positions while campaigning for other offices.
At least the public has been consistent. Resign-to-run was put to voters in 2007. It failed then, too.
Only two measures on the Philadelphia ballot in the past dozen years have been rejected - and both involved eliminating resign-to-run, according to Ellen Kaplan, vice president and policy director for the good-government group Committee of Seventy.
"City Council is increasingly using the charter-amendment process to chip away at the strong-mayor form of government, which was created in the 1951 charter," she said.
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