In a statement on Monday, the BBC said that its decision to purchase and use a botnet to espose the malware epidemic had been in the public interest It was not our intention to break the law, the BBC told ZDNet UK. There is a powerful public interest in demonstrating the ease with which such malware can be obtained and used; how it can be deployed on thousands of infected computers without the owners even knowing it is there; and its power to send spam e mail or attack other websites undetected.
Source: https://threatpost.com/bbc-paid-few-thousand-dollars-botnet-031609/72415/