Can an attorney list a specialty on their webpage? If so, are there special rules that have to be followed?

It depends on your State Bar's laws. In CA the word "specialty or specialist" can only be used if you have passed a Legal Specialization Exam. I hope this helps.

As noted, whether the word specialty can be used will depend on the Virginia or other governing rules of professional conduct. See this link for more information - http://www.vsb.org/pro-guidelines/index.php . In California you cannot say you are a "specialist" unless you are certified in a certain area. I can say with confidence that I doubt it be acceptable under any states rules to say you are "certified" in an area without actually being certified. Good luck.