They're also not mutually exclusive. Someone willing to attack another for partisan reasons could also have a history of "lewd and violent incidents".

Because if you say "rifle" and it turns out to have been a shotgun or a carbine or whatever-the-fuck-else that just looks like a rifle to the guys who witnessed it from 20 yards, you'll have a bajillion gun nuts shattering their teeth in rage and playing pedant. Vague terms like "long gun" allow for the basics of a story to be communicated while the details are worked out with time.