On the opening day of law school, I always counsel my first-year students never to support a law they are not willing to kill to enforce. Usually they greet this advice with something between skepticism and puzzlement, until I remind them that the police go armed to enforce the will of the state, and if you resist, they might kill you.

I wish this caution were only theoretical. It isn't. Whatever your view on the refusal of a New York City grand jury to indict the police officer whose chokehold apparently led to the death of Eric Garner, it's useful to remember the crime that Garner is alleged to have committed: He was selling individual cigarettes in violation of New York law.

The obvious racial dynamics of the case — the police officer, Daniel Pantaleo, is white; Garner was black — have sparked understandable outrage. But, at least among libertarians, so has the law that was being enforced. Wrote Nick Gillespie in the Daily Beast, "Clearly something has gone horribly wrong when a man lies dead after being confronted for selling cigarettes to willing buyers." Republican Senator Rand Paul of Kentucky, appearing on MSNBC, also blamed the statute: "Some politician put a tax of $5.85 on a pack of cigarettes, so they've driven cigarettes underground by making them so expensive."