Trump said this to a lot of people, and although it's not necessary to prove criminal intent, it ought to suffice along with everything else. This is from page 128 of @JonLemire's new book.
See also this report from the day before the insurrection: "According to three people who have spoken to Trump..., with one conversation occurring a week ago. Trump admits his defeat." politico.com/news/2021/01/0…
And this quote attributed to Trump: "Can you believe I lost to that f**king guy? That f**king corpse?" axios.com/2021/01/17/tru…
Also: "Trump has told several people privately that he would rather lose with people thinking it was stolen from him than that he simply lost." (h/t @gtconway3dg) nyti.ms/2Lmgvry
As I wrote here in January 2021, if "Trump has privately admitted that he knows he lost the election ... , he has a big problem: His acknowledgment of defeat refutes any innocent intent."
"Intent can be inferred based on a defendant’s actions. Here, as his followers stormed the Capitol, Trump watched it happen on television and appeared to be delighted. He resisted appeals from multiple sources to try to stop it."
"Even when he finally filmed his video message, he offered words of encouragement to the rioters and told them he loved them.
"These are not the actions of a man who was misunderstood by his followers and is horrified by what they did." sidebarsblog.com/trumps-inactio…
"If the assault on the Capitol was not what Trump intended, any rational person would expect him to act immediately to try to stop it. That he failed to do so is evidence that he supported what was happening." sidebarsblog.com/trumps-inactio…
"There was a lot of love. I've heard that from everybody. Many, many people have told me that was a loving crowd."
—tfg, referring to the crowd at the Capitol on 1/6/21, lto @CarolLeonnig and @PhilipRucker in "I Alone Can Fix It"
"The sources tell CNN that stories circulated about the incident — including details that are similar to how former White House aide Cassidy Hutchinson described it ... — in the months immediately afterward the US Capitol attack and before she testified this week."
"Like Hutchinson, one source, a longtime Secret Service employee, told CNN that the agents relaying the story described Trump as 'demanding' and that the former President said something similar to: 'I'm the f**king President of the United States, you can't tell me what to do.'"
"'He had sort of lunged forward — it was unclear from the conversations I had that he actually made physical contact, but he might have. I don't know,' the source said."
That said—and obviously I defer to the mental-health pros—but the ones I have talked to would likely say: He's not psychotic, but he is at risk of psychosis, as many extreme narcissists can be—and it's not inconceivable he may have had a psychotic episode on January 6.
He was certainly decompensating rapidly on Jan. 6.