The “principle of proportionality” is a useful tool for evaluating laws and public policy. It suggests that the remedy should not create more problems than it solves.
Put another way, the principle means: “Thou shalt not use a sledgehammer to kill a fly.” Moreover, in assessing whether a law’s impact is proportionate, we must take special care to weigh its impact on those who have a special claim on our concern: the poor and marginalized in our society.
The principle of proportionality can be quite helpful when applied to proposals to require law-abiding citizens to produce a photo ID card prior to voting in Wisconsin.