Advice for judiciaries
Deniability of audio recordings by living people
Recordings of that sounds like someone saying something may not be genuine and therefore the suspect should be allowed to state to the court "I did never say that thing you got on tape."
Proving denied audio recordings
If media forensics proves beyond suspicion the genuinity of the media in question or if credible witness to its creation is found, the media should be considered proof of person X having actually said that to a microphone.
Deniability of still pictures and video by living people
Pictures and videos that looks like someone doing something may not be genuine and therefore the suspect should be allowed to state to the court "I am not in that image/video."
Proving denied images and videos
If media forensics proves beyond suspicion the genuinity of the media in question or if credible witness to its creation is found, the media should be considered proof of person X having actually had gotten imaged to the media.