A federal judge questions the Trump administration on implementation plans for controversial birthright citizenship executive order as advocacy groups file class action lawsuits in response.

A federal judge has ordered the Trump administration to explain how it will enforce President Trump's executive order seeking to eliminate birthright citizenship.

Birthright citizenship automatically makes anyone born in the United States an American citizen, including children born to mothers in the country illegally. The right was enshrined soon after the Civil War in the Constitution’s 14th Amendment. The U.S. is among about 30 countries where birthright citizenship is applied.