“Compos mentis” … or Non?

“Compos mentis?”
Most of us are not familiar with this phrase but are much more familiar with the phrase “non compos mentis.”
From AI Overview:
“Non compos mentis” is a Latin legal phrase that means “not of sound mind” or “of unsound mind”. It’s used to describe someone who is mentally incapacitated or lacks the mental capacity to make rational decisions or understand the consequences of their actions. 

My question is whether or not an individual can be “compos mentis” some of the time and “non compos mentis” the rest of the time. Is being of sound mind or not of sound mind all encompassing? Can one be of sound mind (compos mentis) some of the time, and not of sound mind (non compos mentis) the rest of the time? And more importantly can these two extremes be present in the same individual during a twenty-four period? To me logic would dictate that it is certainly feasible that within a single twenty-four hour period that both could be present.
I bring this up because of an article I read from the NY Post published on 12/19/24 titled:
“White House aides hid Biden’s apparent mental decline from Day 1 of his presidency, explosive report reveals”
This same article goes on:
White House aides covered up President Biden’s apparent mental decline from Day 1 of his presidency, shielding the aging commander-in-chief from the public and even rearranging his schedule after scatterbrained performances, an explosive report revealed.
According to the Wall Street Journal, a national security official told an aide: “He has good days and bad days, and today was a bad day so we’re going to address this tomorrow.”

Other staffers removed negative reports from Biden’s stack of news for the day, misleading him about the public’s opinion of his job performance — which reached a 70-year low in 2024.

Meetings were often scheduled for later in the day — a fact first disclosed after Biden’s debate flop against President-elect Donald Trump, when staff admitted the then-Democratic nominee had difficulty functioning outside a six-hour window that closed around 4 p.m. daily.

So continuing on the “compos mentis” vs “non compos mentis” theme, in which frame of mind was Joe Biden in when he pardoned his son for all things going back ten years? Did he do this after 4pm?
Furthermore, in what frame of mind vis-a-vi “compos” vs “non compos” was Joe Biden in when he commuted the jail sentences of nearly 1,500 people and granted 49 pardons, marking the largest single-day act of clemency in modern history? Was this done on one of his “good days” or one of his “bad days?”
In the same vein are we to suppose that all of the presidential mandates that he made over the last four years were done only before 4pm on his good days?
Oh what a tangled web those at the White House have weaved!
12/20/24