"The use of force must be considered an exceptional measure, not to be executed arbitrarily. It should be proportionate to the threat, minimizing damage and injury, and used only to the extent required to achieve a legitimate objective. National legislation should clearly establish circumstances justifying its use. This includes providing adequate advance notice and using only the level of force needed to deal with various threats. Authorities should develop a range of responses to enable a differentiated and proportional use of force."