A California federal judge grilled government lawyers Monday over a Trump administration rule barring asylum for migrants who cross the southern border outside of ports of entry, specifically focusing on whether the change will affect asylum-seekers with legitimate cases and if it conflicts with earlier rules set by Congress.

In the hearing, Judge Jon Tigar of the U.S. District Court for the Northern District of California pushed both sides on whether a recent proclamation from President Donald Trump and an interim final rule from acting Attorney General Matthew Whitaker and Department of Homeland Security Secretary Kirstjen Nielsen would impact migrants who would have been “granted asylum under existing law but who would have been denied asylum under the new rule” and whether there is a correlation between weak asylum cases and non-port of entry crossings that justifies the new rule.