E.i. Du Pont De Nemours & Co. V. Train (1975)

These memos inform the Court whether a justice is "out" for a case; the memo may ask the opinion author to note the justice took no part in consideration of a case; memos may inform the Court that a justice is participating (e.g., not out; not recuse); memos may concern whether a justice should recuse himself or herself (e.g., may recuse self; have not decided whether to participate; do not think I should recuse); memos written by other justices about a colleague's recusal