"There is no good way to ask this without sounding like a jerk, but here it is: Do disabled people really need free parking?" asks Emily Badger. "Yes, they need convenient parking spaces. But cities all over the country have oddly conflated drivers in need of close curbside access with people too poor to pay for it. The two groups are not necessarily one and the same. Worse, free parking for the disabled invites all kinds of wildly offensive misuse. As a result, the policy is arguably bad for urban parking systems, definitely bad for city coffers, even bad for the environment."
"The best evidence we've seen for this politically touchy case comes from some fascinating ongoing research out of the University of California Transportation Center, by Michael Manville and Jonathan Williams." Badger examines the findings reported in an article published by the two in ACCESS, the transportation center's magazine.
"Manville and Williams aren't arguing that we should abolish disabled parking all together. Rather, they argue that there's no good reason to make it free, and plenty of reasons not to."