Customs and Border Protection (CBP) officers pre-screen foreign nationals traveling to the United States using IT systems to check passenger manifests against intelligence and law enforcement databases. But the Department of Homeland Security’s (DHS) Office of the Inspector General (IG) recently found that, “poor performance of a critical pre-screening system hindered the ability of [CBP] officers to identify individuals who could pose concerns, including national security threats.”

In plain English, CBP’s computers crashed. It was flying blind. And CBP officers were forced to rely on backup systems that the IG says, “weakened the screening process” and possibly led “to officers not being able to identify travelers that may be attempting to enter the United States with harmful intent.”  That’s scary! It means that criminals and terrorists might have been able to slip past immigration controls because vetting databases were unavailable when officers needed them most.

Why did the systems go down? Starting in May 2015, CBP rolled out a new platform to improve access to information systems – located both inside and outside the Department of Homeland Security – that share law enforcement data. Rather than speeding up, however, CBP’s computer terminals slowed down to speeds associated with dial-up internet. According to the IG, the time required to conduct pre-landing checks on commercial airline flights increased from five minutes per airplane to 30 minutes per airplane.

This is only the latest in a series of ongoing vetting problems experienced by DHS. U.S. Citizenship and Immigration Services (USCIS), the agency responsible for vetting naturalization applicants has experienced similar IT-related problems. A September 2016 internal audit found that USCIS appeared to have erroneously granted citizenship around 900 ineligible immigrants because electronic data files contained incomplete fingerprint entries.

The Trump administration has acknowledged the obvious problems with current vetting practices – the lack of information available on some travelers and the unwillingness of certain governments to share intelligence with the United States. However, the IG’s report highlights another significant problem affecting vetting: IT infrastructure. Without effective computer networks and easily accessible database systems, it would be utterly impossible to screen the over 300 million short-term visitors, and one million plus immigrants, who come to the United States each year.

If President Trump really wants to implement extreme vetting, then he needs to lead an extreme change in the way DHS maintains its information systems. We can gather all the data we want on criminals and terrorists. But if crumbling IT networks and outdated databases keep immigration officers from accessing that information our vetting won’t be extreme, it will just be extremely poor.