Among other changes to immigration law, the measure would make it more difficult to gain asylum in the United States and increase detentions and deportations of those crossing into the country without authorization. It would also effectively close the border altogether if the average number of migrants encountered by immigration officials exceeded a certain threshold — an average of 5,000 over the course of a week or 8,500 on any given day. The bill also would give the president power to close the border unilaterally if migrant encounters reach an average of 4,000 per day over a week.