According to internal documents and staff emails obtained Tuesday by The Washington Post, the asylum officers will more aggressively challenge applicants whose claims of persecution contain discrepancies, and they will need to provide detailed justifications before concluding an applicant has a well-founded fear of harm if deported to their home country.

The changes require officers to zero in on any gaps between what migrants say to U.S. border agents after they are taken into custody and testimony they provide during the interview process with a trained asylum officer.

“Officers conducting credible fear interviews should also be addressing any more detailed inconsistencies between the applicant’s testimony during the credible fear interview and other testimony in sworn statement,” John Lafferty, the head of the asylum division at U.S. Citizenship and Immigration Services (CIS), wrote to staff in an email, outlining the changes.