TWO DECADES AGO, my father, then in his mid-seventies, used to fly to the northern New South Wales town of Lismore several times a year. He would buy $10,000 worth of marijuana, store it in his carry-on luggage and return to Sydney the same day.

A lifelong user, he had started dealing in order to supplement both his habit and his old-age pension. At the time, I considered him an entrepreneurial anomaly, but these days more and more Australian pensioners are cultivating and/or selling illegal drugs. Anecdotal evidence suggests that some do it for the promise of regular visitors, others to fund hobbies, others to be able to afford to self-medicate. Most, however, seem to be happy to be on the wrong side of the law for the chance to top up their pensions with tax-free cash.