One of the US Drug Enforcement Agency’s most wanted, a suspected drugs baron nicknamed Lollipop, has given one of the most rigorous assessments of biometric security technologies ever conducted.

Thanks to a Bond-villain-like commitment to facial plastic surgery and a collection of false identities that Carlos the jackal would have envied, Juan Carlos Ramirez Abadia had successfully eluded the DEA. But there was one thing he could not change: his voice. In August 2007, US officials used this to finally get their man.

By tapping the Lollipop’s telephone conversations, agents could compare Ramirez Abadia’s ‘vocal fingerprint’ to previous recordings that had been made by Colombian authorities. There were sufficient recordings to develop a sophisticated map of the suspect’s vocal characteristics which, when compared with the phone-tap evidence, provided enough grounds for identification to get an arrest warrant.

Ramirez Abadia, accused of being the head of a cartel responsible for importing over 550 tons of cocaine into the US and reported to have amassed a personal wealth of $1.8 billion, was tracked to one of his luxury Brazilian properties and arrested.