If Pittsburgh's political history teaches us anything, it's this: You can never have too many politicians. Why else would we have 130 municipalities in Allegheny County alone, each with its own bevy of officials? Because our ancestors wanted us to govern the heck out of each other, that's why.
So yes, Pittsburgh did used to have aldermen, but they were not city councilors. Unlike in Chicago, where the city's legislators are still called "aldermen" today, Pittsburgh's aldermen acted as municipal court judges. In later years, much of their function was assumed by city magistrates appointed by the mayor.
The office of alderman was created at the same time the city itself was: In 1816, Pittsburgh's original city charter established a many-headed hydra of government. It featured a mayor, a recorder, 12 aldermen, and not just one but two city councils: the "Select" and "Common" councils, which boasted two-dozen members in all.
Originally, only councilors were elected by voters. The recorder and alderman were appointed by the governor, and in the words of the charter, they were allowed to "hold their offices during good behavior." Given the disrepute of 19th-century Pittsburgh politics, that probably would be about 15 minutes in some cases. But in any case, one alderman was chosen as mayor by the councilors; the lucky winner served in both the executive and judicial branches.
According to Frank C. Harper's history Pittsburgh of Today, aldermen were initially given "full power to try and determine all forgeries, perjuries, assaults and batteries, riots, routs and unlawful assemblies ... and also all violations of [local] ordinances." In what were called "Mayor's Court" proceedings, they could convene juries much like any other court, and try some civil and criminal cases.
Such a court no doubt sounded useful: If nothing else, its jurisdiction over "routs" might have resulted in a court order to stop the Christmas Eve Steelers/Ravens game early. And it made sense for a large city like Pittsburgh to have a separate court ready to handle traffic offenses and other local ordinances.
On the other hand, in recent years there have been spirited arguments about why both the city and the county treasurers were issuing dog licenses. So you can imagine the complications that might arise when the city was operating its own judicial system.
Not surprisingly, over the following decades, the aldermen's power was diminished greatly. In 1833, the city charter was amended so that the mayor could be elected directly by the people, with alderman and councilors taken out of the equation entirely. Six years later, the "Mayor's Court" was abolished, though aldermen still had the ability to rule on minor infractions.
Meanwhile, the other branches of city government kept growing. After Pittsburgh's 1907 annexation of the North Side, the city's Select and Common councils had 100 members between them. (It was shrunk to the current nine-member body shortly afterward.) The mayor, meanwhile, became more powerful thanks to numerous government reforms -- not least among them the ability to appoint city magistrates, who assumed the responsibility for conducting preliminary hearings and trying minor offenses.
In most of Pennsylvania, responsibility for handling routine court actions -- like preliminary hearings, minor civil and criminal disputes, landlord/tenant arguments and so on -- are handled by district justices. Yet while Pittsburgh had such justices, much of that work was handled by the mayor's appointed magistrates. In 1967, Pittsburgh gave its magistrates added responsibility for housing-code violations, whose prosecution had previously been scattershot. And in 1968, a statewide constitutional convention restructured the entire state judicial system ... but allowed that in Pittsburgh, "magistrates, including those serving in the traffic court, the housing court and the city court shall continue as at present."
But political forces were arrayed against the city magistrates. Local district justices waged a turf war against them: They claimed the magistrates were redundant, while skeptics claimed the DJs just needed to justify their own jobs.
In the end, the DJs won: In the latter years of Tom Murphy's fiscally troubled administration, the state cut off funding to the system, and it was disintegrated in 2005. Responsibility for housing violations and the like was transferred to district justices, and complaints about uneven enforcement of housing codes began shortly after. Maybe there's something to be said for redundancy in government after all.