The police in Italy are highly annoying. And they have whistles.
At the Trevi Fountain in Rome cops whistled at us when we bit into ice cream cones too near the water -- though a disgusting dog was allowed to lap at the fountain without penalty. At the Victor Emmanual Monument they went nuts with their whistles when we sat on a bench near the Tomb of the Unknown Soldier.
Then in the Campo, the large rounded piazza around town hall in Sienna they whistled when tourists reclined on the stones. Apparently you can sit on the stones. You can run on the stones. You can kneel on the stones, but you can't recline on the stones.
This inspired us to break the law flagrantly. Two Americans sitting behind us found that highly amusing.