Merchan was the judge in the Trump NY money laundering case. He's the one where Trump alleged his daughter was so anti Trump that Merchan himself needed to recuse himself from the money laundering and bribery scheme.
After Trump was convicted Merchan stalled for months on sentencing and finally SCOTUS gave Trump immunity and then when Trump won the election, Merchan effectively dismissed the case without sentencing. Merchan said he was waiting to sentence to see how things played out.
It's not leaked out that after the verdict they did the pre sentencing psych exam which is standard. Trump scored 36 out of 40, so genius right? Well no, the test is a "dangerousness" exam the idea is anything above 30 the judge is recommended to sentence the person to hospitalization. This was 2024 so Trump is much worse but 2 years ago Merchan SHOULD have had him entered into a hospital, not necessarily committed but put in because he was a clear danger to the public. Merchan, much like Merrick Garland, didn't want to appear biased so he waited and then SCOTUS screwed us all over with the immunity ruling.
Psychiatrist Bandy Lee went public with it saying Trumps score, anything over 30 is clear indication of clinical psychopathy and hospitalization is generally recommended. She has never personally examined Trump but given he got 36 2 years ago she said he likely would score as close to 40 as is humanly possible now.