The former Government drugs tsar, Professor David Nutt, has said the financial crisis was caused by too many bankers taking cocaine.The controversial academic, who was sacked for claiming that ecstasy was as safe as horse riding, told the Sunday Times that abuse of cocaine caused the financial meltdown."Bankers use cocaine and got us into this terrible mess," he told the paper adding that the drug made them "overconfident" and led to them taking more risks.