Starting in May, Chinese citizens who rank low on the country’s burgeoning “social credit” system will be in danger of being banned from buying plane or train tickets for up to a year, according to statements recently released by the country’s National Development and Reform Commission.

With the social credit system, the Chinese government rates citizens based on things like criminal behavior and financial misdeeds, but also on what they buy, say, and do. Those with low “scores” have to deal with penalties and restrictions. China has been working towards rolling out a full version of the system by 2020, but some early versions of it are already in place.

Previously, the Chinese government had focused on restricting the travel of people with massive amounts of debt, like LeEco and Faraday Future founder Jia Yueting, who made the Supreme People’s Court blacklist late last year.

The new travel restrictions are the latest addition to this growing patchwork of social engineering, which has already imposed punishments on more than seven million citizens. And there’s a broad range when it comes to who can be flagged. Citizens who have spread “false information about terrorism,” caused “trouble” on flights, used expired tickets, or were caught smoking on trains could all be banned, according to Reuters.

But the system, as it stands, is opaque; citizens are seemingly just as likely to be flagged for minor infractions like leaving bikes parked in a footpath or issuing apologies that are deemed “insincere” as major credit defaulters like Jia. And it’s often unclear whether they’re on a blacklist in the first place, let alone what kind of recourse is available. “Chinese government authorities clearly hope to create a reality in which bureaucratic pettiness could significantly limit people’s rights,” Maya Wang, senior researcher for the non-profit NGO Human Rights Watch, wrote in December.