An action that Trump has discussed since the beginning of his administration, it will be spearheaded by Vice President Mike Pence and controversial Kansas Secretary of State Kris Kobach.

Kobach, who helped on the Trump transition team, is a lightning rod for critics who have accused him of extreme racism and having ties to white nationalists.

Kobach is almost single-handedly responsible for some of the nation’s strictest immigration laws in at least a half-dozen states — he not only writes the laws, but advocates for them and battles on their behalf in court. He is often cited as the chief architect of what Arizona’s SB 1070, which was passed in 2010 and led to protests and state boycotts for encouraging the profiling of Latinos and other minorities.

The Arizona law requires police to determine a person’s immigration status when there is “reasonable suspicion” that they are not legally in the US; it was partially upheld by the Supreme Court, but had other sections struck down by the court in 2011.