conrad murray & michael jackson*After getting a cease and desist notice from the Michael Jackson estate, Conrad Murray seems to be playing hardball.

He’s reminding everyone, including the estate, that they were the first ones to open the can of worms that is MJ’s medical secrets.

As we reported, the MJ Estate is threatening to sue Murray for talking to the media … in particular, Australia’s “60 Minutes” program … about MJ’s medical details — including a story about holding the singer’s penis every night. The Estate is claiming Murray has been violating the doctor-patient privilege by running his mouth in public.

But Murray is not particularly scared because once Katherine Jackson sued for wrongful death (and exposed MJ’s medical secrets at the trial), she compromised the doctor-patient privilege on her son’s behalf.

Murray’s team tells TMZ that the used-to-be-doctor believes the information the estate is trying to protect is, at least generally speaking, already out in the public and was exposed during the AEG wrongful death trial. Bottom line, except for a few specific details, he’s not saying anything new.

Hmm, we shall see.