Intervention ladder
A scale of policy options ranked from least to most intrusive on liberty.
What it means
The intervention ladder is an ethics framework that ranks ways of influencing behavior by how much they intrude on individual liberty, from the least to the most coercive. Its rungs ascend from 'do nothing or simply monitor,' through providing information, enabling choice, guiding choice through changing the default, guiding choice through incentives, and guiding choice through disincentives, up to restricting choice and, at the top, eliminating choice altogether. The framework's purpose is normative rather than descriptive: it provides a structured way to deliberate about the proportionality of an intervention, embodying a presumption in favor of the least intrusive option that will achieve the desired public good, with stronger justification required as one climbs. It pairs naturally with libertarian paternalism, since nudges (such as changing defaults) sit on the lower-to-middle rungs and preserve freedom of choice, whereas bans occupy the top. Its application involves genuine judgment and debate — weighing effectiveness, the severity of the problem, fairness, and the costs of inaction against the loss of autonomy. It matters because it gives policymakers in public health and beyond an explicit, defensible vocabulary for choosing and justifying how forcefully to intervene.
Examples
To curb unhealthy eating, prefer clearer food labeling (a low rung) before considering taxes (a higher rung) and an outright product ban (the top rung), escalating only as justified.
To cut speeding, a council starts with signs that flash your speed back at you, then moves to average-speed cameras, and only then to narrowing the road itself.
An employer wanting fewer late-night emails first publishes guidance, then makes delayed-send the default, and treats switching the mail server off out of hours as a last resort.
First described in Nuffield Council on Bioethics (2007).