Tuesday's New York Times ran an article (subscription req'd) on people who are denied access to health-related info (for themselves or family members) due to medical personnel not knowing how to interpret HIPAA regulations. HIPAA is one of the key pieces of US legislation governing privacy of medical information. Medical personnel apparently deny access in many cases that HIPAA would allow because the boundaries of the law are either unclear or unknown to the personnel.
Given the liability involved, denying access is an obvious default. Denying access beyond the intent of the policy becomes problematic, however, when it prevents people from getting information they need in order to get something legitimate done. The balance between protection and availability is hard to get right. When the people charged with enforcing the policy are unclear on its scope, the balance skews towards protection and more legitimate tasks are prevented. HIPAA permits but does not require a wide range of requests for information, so many err on the side of caution and choose not to disclose (sometimes for other reasons but using HIPAA as an excuse). Disclosure policies are left to individual health providers.
The real problem here then, is not one of people not understanding HIPAA, but one of people not understanding that HIPAA is a _component_ of health information policy, but not the entire policy. Language standards for writing access-control policies, such as XACML, have evolved to support policies that handle some issues but not others. If one were to encode HIPAA in XACML, most of the disclosure cases would produce a decision called "not applicable", instead of one called "deny". This would enable the hospital to write its own policy for the disclosure cases. The hospital's overall policy would be a combination (technically, composition) of the HIPAA and local policies. Either sub-policy could issue a decision on a request for information, using the "not applicable" answer to say "this is outside my scope, let the other policy decide".
In short, HIPAA is a fantastic example of why policies need to have three possible decisions (permit, deny, not applicable) rather than just two (permit, deny). Practioners are defaulting what should be not applicables to denies and skewing the intent of the policies. Fixing this requires making people aware that HIPAA governs only a fragment of information access issues and having them learn the local policies as well as the federal one. With only a couple of policies, this isn't hard, but it is subtle: one policy is rarely enough. The trap is that, since it looks like a complete policy, is gets overapplied. The policy language has to be subtle enough to distinguish "required" from "permitted" from "disallowed". The language is there, but its subtlety, and hence information access, is seemingly lost on many people.