Mexico Challenges Arizona's Immigration Law

BBC reported that: Mexico has waded into a legal challenge to a new immigration law in the US state of Arizona. In papers submitted to a US federal court, the Mexican government argues that the law is unconstitutional and would damage bilateral relations. It says it is concerned that it could lead to unlawful discrimination against Mexican citizens. The law - which comes into force on 29 July - makes it a state crime to be in Arizona without immigration papers. It also requires police to question people about their immigration status, if officers suspect the person is in the US illegally, and if they have stopped them for a legitimate reason.