This is an interesting article about declawing in the San Francisco papers. San Francisco, is known to be one of the more progressive cities in the US in terms of animal welfare, and their SPCA is world famous.
Interestingly, the SF SPCA and some of the vets do not want to ban declawing. One of the reasons given is that they do not believe city council should legislate on the matter. Another is that there is a worry that owners might give their cats up if they are not given the option of declawing.
A couple of issues - again, I'm not a huge fan of unnecessary legislation as you guys know. Often, without enforcement, how effective is it just to HAVE a law? However, a few years ago when we considered this topic, we talked to the vets in Singapore. Instead of having a strict law against it, the vets, as a body, could decide amongst themselves NOT to practice declawing. That way, if there were also very specific reasons why they might want to practice declawing in certain cases, they can still make that decision. For example, if someone comes to them and says that their cat has scratched them and the cat will be tossed out on the street otherwise.
On the other hand, some of the vets told us they thought that cats might be thrown out on the streets otherwise. First of all, even in Singapore, where declawing is not very common, we have found declawed cats abandoned. So I don't think that argument holds much water. Secondly, most people declaw cats when they first adopt/buy a cat, so it would not really affect that many people who already HAVE cats. If it stops someone from adopting a cat, then so be it. Also, as I mentioned, if it is a practice direction that the veterinary association agrees to adopt, then they CAN make exceptions where they think it is necessary.
Another point I think to consider is that declawing has been illegal in the United Kingdom and I believe much of Europe for many years as has tail docking. If it has worked there, then I think it's high time to consider doing away with the practice - whether by law, or by internal regulation.