Not to say it couldn't happen, but that moral numbing is more likely to be sexual "mistakes," or blowing off a previously made commitment, or lying about why you are not where you are supposed to be, or leaving worthless scumbags in your life that you would never even consider as friends if they weren't your smoking buddy or your source.
Again, I've never seen someone get violent on dope, and I've seen a lot. Now, if it's got something weird on it, like angel dust, or if the person is also on speed, or drunk, well, then I don't blame the THC.
Now, I will say that people who are detoxing off any drug tend to be a little cranky, and might be short-tempered.