In early 2012, I wrote a post titled “Speeding Fines that Vary with Income: Absolute vs. Relative Risk Aversion and Public Policy,” about income-proportional speeding tickets.
In light of the best evidence on the relationship between risk preferences and income–which essentially finds that as people get wealthier, they care less and less about gambling over a fixed dollar amount (say, $200), but their aversion to gambling a fixed fraction of their income or wealth (say, 1% of their income)–I explained that instead of fining people a fixed dollar amount for speeding, we should fine them a proportion of their income. In practice, this could be done by using a person’s declared income for the last year by checking with the IRS or with the department of revenue in the state where a person gets fined. In my post, I wrote: