Washington Post: The Obama administration is escalating its crackdown on tough immigration laws, with lawyers reviewing four new state statutes to determine whether the federal government will take the extraordinary step of challenging the measures in court.

Justice Department lawyers have sued Arizona and Alabama, where a federal judge on Wednesday allowed key parts of that state’s immigration law to take effect but blocked other provisions. Federal lawyers are talking to Utah officials about a third possible lawsuit and are considering legal challenges in Georgia, Indiana and South Carolina, according to court documents and government officials.

The level of federal intervention is highly unusual, legal experts said, especially because civil rights groups already have sued most of those states. Typically, the government files briefs or seeks to intervene in other lawsuits filed against state statutes.