Last year almost 16m guns were sold in the United States. According to a government survey, 16% of adults have used marijuana in the past month. People buying a gun must fill in a seven-page federal form. Question 21f asks: “Are you an unlawful user of, or addicted to, marijuana” (or any other illegal drug)? Almost certainly hundreds of thousands of people lie on the form, which is a felony. In a typical year, fewer than 300 are prosecuted.

This year Hunter Biden became one of them. On June 11th the president’s wayward son was convicted on all three charges against him, after a six-day trial. In October 2018 he bought a Colt revolver at a gun shop in Wilmington, Delaware. At the time he was, a jury decided, addicted to crack cocaine. In theory he could now be sentenced to as long as 25 years in prison.