The public must be provided a reasonable access to all records public.

Does the sealed documentation need to be unsealed even if only the defendant wants to inspect or obtain copies of any such records? And if so, why?

Presume Bob is accused maliciously of a crime abetted by the police, and video records _may_ have corroborating or direct evidence of this that it recorded on its AXON.

The AXON video is reported to have been created by the police and alleged to have been turned over to the DA.

The DA provided all evidence to the defense except that video.

Appointed counsel is conspired, and plays in the hand of the DA in not requesting the DA to hand over the specific evidence despite the written request of Bob that the appointed counsel acknowledged in writing and generally denied.

Bob clearly is unable to build an affirmative defense based on the otherwise well-corroborated conspiracy because app. counsel denies to obtain and/or present let alone provide a copy of the AXON (redacted per Pen. Code or otherwise).

Does Bob, for example due to a fair trial, to a just outcome, to effective assistance of counsel, to the right to raise concerns about the effective assistance of counsel under a Marsden motion or based on any other well-established case law or legal theory on statute, the constitution or any treaty, have a right to be presented such evidence or obtain a copy before a pre-trial conference _directly_?

It is only in the possession of the DA and the police. 

Destroying the evidence will make it much more obvious than keeping Bob silent having an appointed counsel who will simply be able to assert he didn’t believe the evidence pertinent to the case than explaining why only that piece went missing should the DA asserted that.