@dushman >Definitely don't download those decryption keys that would violate copyright law
Actually, I don't believe decryption keys even qualify for copyright law, as such is really non-creative information in a set format.

The collection of keys as a whole may qualify for copyright and I don't see a license on the collection, but as the collection is publicly available, downloading it is authorized, but sharing the collection further may not be.

The law that you may infringe by downloading the keys and shattering digital handcuffs is the DMCA (they call it the "copyright act", but it's really something completely different).

You might want to also download prebuilt BD+ tables - as although libdbplus can run the proprietary software from the bluray to uncorrupt the video and audio, you don't want to do that.