Earlier quoted context omitted.
Depends on where in the world you live. Also depends on the kind of misconduct. In general I'm of a mind that it isn't any of my employer's business what I get up to when I'm off the clock. If they can define "misconduct" in a sensible way they're probably free to add it to my employment contract, in which case I can decide for myself whether or not to work for them. Anything less is arbitrary nonsense and will likel…
There's such a huge grey area, though. On one extreme: I work at a desk job and it'd be insane for my employer to fire me for getting a speeding ticket doing 70 in a 65 zone. On the other: if I were shown in a CNN video carrying a swastika flag in a parade, I absolutely 100% expect I'd be jobless by the time I got home. I wouldn't pause for a moment at an employment contract that says the latter violates their rules.
Because it isn't ever actually carrying a swastika flag. It's supporting the opposite side of a current contentious issue like abortion.