The riot shotgun is a 12 gauge shotgun in Syphon Filter: Omega Strain which uses bean bag ammunition.
"This is a modified combat shotgun that fires bean bags instead of standard shot. The bean bags inflict a non-lethal, though extremely painful, shot. Users of this weapon are cautioned against head and neck shots because they will cause severe brain trauma and, in many cases, death to the victim."
- Description from Omega Strain
In game uses
This weapon is obtained by earning Mujari's commendation. Argubly it is inferior to high damage shotguns because it only knocks enemies out; but technically shotguns are lethal in close range. This shotgun suffers from further disadvantage because one must be very close to a victim to kill him (it cannot pierce body armour).