A MCDONALD's Big Mac is a greater threat to public health than cannabis - and Ireland should lift its ban on hard drugs, a controversial former American law enforcement official declared yesterday Ex-US police chief and anti-prohibition campaigner Jerry Cameron urged the Government to legalise marijuana and heroin if it wanted to win the war on drugs. But he drew the ire of anti-drugs campaigners who called for an investigation into his appearance at a public forum in Dublin. [continues 310 words]