Depends on how aggressive they are.. and maybe a wee bit on what they are protesting about, and related to how I feel about being a riot policemen. If it's armed neo-nazis wanting to kick out 90% of the country to live like kings, then I'd sneak some live ammunition in. If they happen to be fairly peaceful protesters hen I'd have to question the motives of the police officer in charge. It's not likely to happen as police officers with power generally don't abuse (some do, but not that many).