Peston didnt lie but released sensitive information that was negative to the company involved. at the time it was suggested that his releasing the news precipated the actions taken, changing the options available to BoE and government. im not saying he cause the crash, Lehman had already...
its a balance. public interest has to be weighed against the broader impact of the infomatino being public. its not in the public insterest to have a run on the banks for example, or say have a stock market crash due to some improperly released information.
HBOS nearly when bust when Peston published sensitive leaked information for the sake of a scoop - the information would have been public within a day but in a more controlled manner. point is, journalist must take some responsibility with leaks that may have major impact, and as they cant be...