When states repeal or weaken motorcycle-helmet laws, as dozens have, helmet use falls, fatalities rise and head-injury hospitalisations soar. Biker deaths rose 18% after Michigan repealed its all-rider helmet law in 2012. A rule obliges unhelmeted Michigan riders to carry at least $20,000 in medical-payments coverage. That does not even cover initial stabilisation in intensive care after a nasty crash... Deaths-per-bike-mile rose 25% when Texas scrapped helmets, for instance. In Washington Tom Petri, the Republican chairman of the House of Representatives committee that oversees highways, wants the CDC to stop researching motorcycle safety. The agency seems to have “an anti-motorcycle agenda”, he growls. Asked about accidents involving the helmetless, he says: “I don’t think there’s that clear a correlation.”