Monday on MSNBC’s “The Beat,” actor and director Rob Reiner said during the 2016 presidential campaign when news reports came out about President Donald Trump using an alias when calling reporters, he knew Trump was “certifiably insane.”

Reiner said, “OK, so first of all, it was him on the phone. When I heard this, this was during the campaign. I learned about this, this habit that he has of going on and talking as this guy John Barron, or one of these other characters, I thought to myself, this guy is certifiably insane. Because think about this for a second. Who do you know that gets on the phone and pretends to be somebody else on this kind of level and talks to a journalist to get information out? That’s insane. That’s insanity.”

He continued, “I thought when I heard that, how can that guy be president? How are we going to allow a person who does a thing like that become president of the United States? And, you know, it happened. But that’s as crazy — that’s kind of beyond pathological. There’s some kind of mental illness that allows for something like that to happen.”

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