GOP governors from more than a dozen states are backing the Trump administration in its lawsuit over California's sanctuary cities.
The White House filed the lawsuit that says three California state laws that protect illegal immigrants undermine national immigration laws.
The Justice Department called the laws unconstitutional. Federal officials say the law has allowed California officials to prevent authorities from removing dangerous people who are in the U.S. illegally.
GOP leaders say California's laws could harm their states too by making it easier for immigrants who have committed crimes to move to other states.
The states filing the lawsuit are Texas, Alabama, Arkansas, Florida, Georgia, Indiana, Kansas, Louisiana, Michigan, Missouri, Nebraska, Nevada, Ohio, Oklahoma, South Carolina and West Virginia.