At least four Mexican journalists have been killed this year for their reporting, according to the Committee to Protect Journalists (CPJ). Since 2007 66 have died violently. On May 15th unknown assassins murdered one of the finest, Javier Valdez, in the state of Sinaloa. Mr Valdez was a co-founder of Ríodoce, a weekly publication that covers corruption and the bloody wars between drug-trafficking gangs. The CPJ says he “combined the grit of the most battle-hardened reporter with the elegiac soul of a 19th-century Romantic poet”. The death toll is so high that earlier this month the attorney-general’s office replaced the chief of its division for “crimes against freedom of expression”.