There is no such thing as a 'government only, and only with a warrant' backdoor. There is either private or not private.
It is possible to design a system where judges have their own hardware keys. Hardware keys can not be cloned assuming strong tamper protection. If a hardware key gets stolen it can be revoked as being valid and a judge can be issued a new one.
DRM is different because the client ultimately has to have the keys to decrypt the content they have been permitted access to.
Who would control the creation of the keys? I mean which tech vender would control access to my android phones encryption? My phone was made in China, and the chips inside it were made in China. They also have the most people, so it seems fair they control the keys.