Sure, it’s a logical fallacy, but I don’t believe this binary is wholly true. A moral failure in any area indicates a likelihood for moral failures elsewhere. This likelihood is not irrefutable evidence, but it is not in any way illogical, either. It’s basic pattern recognition. If you murder once, there is an increased likelihood to murder again. If you do drugs once, there is an increased likelihood to do drugs again. This is statistically proven.

It’s like a corrupted database. Sure, the other data may not be corrupted, but now that there’s proven corruption how am I to know what other data is or is not corrupted? Easier to just restore from backup and move on (in this case your backup is anyone else who is not a fascist).

Of course, I’d probably take Ben Carson’s advice on brain surgery regardless, but that’s because he has undisputed experience in a high skilled field. If he’d been diagnosed with dementia, that does not provide irrefutable evidence against his advice, but I’d probably seek a another opinion. If my GP was fascist, I’d prefer to get recommendations from a different GP.