evidence: - behaviour modification - coercion - technology/risk assessment - philosophical ethics - public health ethics [...] Grave threat to public health [...] As we can see from the previous section and figure 2, there are a variety of coercive measures. (The Nuffield Council has created a related "Intervention Ladder",29 though this includes education and incentives, as well as coercive measures.) Penalties can be high. In war, those who conscientiously objected to fighting went to jail or were forced to perform community service (or participate in medical research). In France, parents were given a suspended prison sentence for refusing to vaccinate their child.30