One route for the smuggling of wildlife parts, such as rhino horn and elephant ivory, could be closed without the need for new international conventions or treaties (B. I. Kaaria and N. L. Muchiri Proc. 9th Int. Conf. Environ. Compliance Enforc. 204–208; 2011). Rogue diplomats must be stopped from exploiting their consular immunity to flout customs regulations and support this illicit trade.

The scale of the problem is unquantifiable, but anecdotal evidence indicates that it is widespread. Diplomatic bags containing horn were reported to be evading customs checks as long ago as the 1980s (E. B. Martin Pachyderm 21, 28–34; 1996). In 2011, a South Korean diplomat was caught smuggling ivory (see go.nature.com/fuo43s).

Countries could adopt the UK practice of giving full immunity only to diplomats who are accredited to that country; others who pass through British territory are subject to regular checks. Because there are few direct flights between African and Asian capitals, diplomats would run the risk of also being checked at European airports when changing flights.

Apprehending diplomats carrying illegal materials would generate negative publicity, forcing countries to punish errant civil servants and reduce the problem. Immunity should not mean impunity.