It has been more than half a century since U.S. immigration laws were written to enshrine the right to apply for asylum at any port of entry to the country. But a new lawsuit argues that today, the right to seek safe haven from persecution is only accessible to people who show up at America’s doorstep with a working smartphone in hand.

Since May, migrants on the Mexico side of the U.S.-Mexico border who are hoping to apply for asylum have been required to make their asylum appointments through a mobile phone app operated by U.S. Customs and Border Patrol, known as CBP One. The new system has effectively oriented the first — and for many, the most urgent — stage of the asylum process around a digital tool that is, by many accounts, glitchy and unreliable.

On July 27, immigrants’ rights groups filed a class action lawsuit against the Biden administration over its use of the app, setting the stage for a legal showdown over the government’s decision to shift the first stage of the asylum application process into the realm of automation.

The plaintiffs include 10 migrants who sought asylum along the border but were turned away by U.S. immigration officials because they hadn’t made appointments using CBP One. Their suit alleges that the U.S. government’s use of CBP One has created steep, and in some cases insurmountable, technological obstacles that have prevented migrants from pursuing their right to asylum. As a result, they’re often left with little choice but to remain in Mexican border towns, where violence and crime targeting migrants is notoriously high.