Parking as a 'common property resources'
-Tragedy of the commons results
-Almost all parking management is based on shifting it from being a common-pool resource to a public good, by increasing excludability.
1) Exclusion through 'club lists' (resident parking permits)
2) Exclusion through pricing (metered parking)
The first is generally seen as more equitable, but the latter is understood to be more efficient. The ethical acceptability ties into the political acceptability. There will be a political backlash against any policy that makes some some people better off while making others worse off, especially if the harms are concentrated and the benefits diffuse. Right now, in Utah, Brigham Young University started to charge to park on campus. Suddenly, all the on-street parking just off-campus is jammed. Residents who were using it are enraged-their free available parking is gone, through no action of their own.
After a few mobs-with-torches situations, politicians get gun-shy about parking. And hence cautious, doing so in limited cases. Rare indeed are cases like Britain (where minimum parking requirements are now forbidden, nation-wide) or the city of Buffalo (where minimum parking requirements have been eliminated city-wide). This sort of disjointed incrementalism should be welcomed: Better some than none. And better to discover potential problems during a test-case, rather than everywhere, all at once.
The 'equitable' approach itself has serious equity issues of its own. Limited passes to those currently parking is unfair, as that is to the detriment of those who are not currently using the parking--it seems only fair that everyone should get an equal number of passes. Doing so vastly undermines the effectiveness of the program. Current parking use is responding to the actual supply of parking. Over-providing permits swamps the supply, doing little to ensure parking availability. It is also inefficient, as residents 'loan' unused parking permits to friends and family, which is neither efficient nor equitable.
Pricing parking efficiently has problems as well. My dad refused to drive downtown, because he wasn't willing to pay for parking. When we did, we parking in strange marginal lots, many blocks from our destination. Berkeley, California, has one of the best, where on-street parking (the most available) was made more expensive, while off-street parking was made cheaper. This both increased the perceived availability of parking, and provided an incentive to go to the (cheaper) garages.