Can someone find where, in the law, authority explains OLC's secret memos?
Here is the OLC page describing the use of memos, which are written to inform the AG.
It mentions that some are withheld from publication. It does not specify WHO makes that determination, or what criteria are used to decide which is secret, or who might decide later that the opinion can be released.
Today, a secret 1994 memo written by Theodore Olsen is used to explain DoJ refusal to charge two coup plotters/actors.
This sounds like a government run by a secret cabal inside the Justice Department -- a cabal that can issue de facto law by fiat, like a papal decree.
[link:https://www.justice.gov/olc/opinions-main|
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"Today, a secret 1994 memo written by Theodore Olsen is used to explain DoJ refusal to charge two coup plotters/actors."
I can't find that reported anywhere 
When was it used to refuse to charge two coup plotters? I can't find that reported anywhere