Per NFL rules, a defender cannot tackle the quarterback low. This is known.
Michael Bennett was flagged for a roughing the passer penalty Sunday against the Vikings for allegedly doing just that on Kirk Cousins.
— The Birds Informer (@BirdsInformer) October 7, 2018
The flag flew it despite the fact that Bennett first even contact with Cousins at his hips, not his lower body.
To avoid a penalty here, Bennet would have had to theoretically wait to get back up to his feet in order to tackle Cousins, all while he’s standing inches away with the ball still in hand.