On May 10, 2018 United States Citizenship and Immigration Services (USCIS) issued a policy memo stating its intent to change the way "unlawful presence" is calculated for people found to have violated the terms of their student and exchange visitor visas (F, J, and M visas). It claims the new policy will help reduce the number of people overstaying those visas. The memo is expected to take effect on August 9, 2018.
Currently, people with F (student) and J (exchange visitor) visas are usually not given an end date on their visas, but are admitted for a period called "Duration of Status" or "D/S." Duration of Status lasts as long as their term of study and other activities associated with those visas, including practical training. Students and exchange visitors can be found in violation of these visas for obvious violations like ending their studies but also for other minor, and sometimes unknowing violations, like failing to pursue the practical training in compliance with USCIS standards.
Under the previous policy memo, a student in a violation of a student visa did not automatically start accruing "unlawful presence" in the United States. Instead, that student was deemed unlawfully present only after an official determination was made that he or she violated the terms of the visa—either by an immigration judge after the person was put into removal (deportation) proceedings (at which time the student or exchange visitor would have a chance to put forward a defense), or by an official USCIS decision, when the student applied for another visa or immigration benefit.
This determination process for unlawful presence for student visas was previously distinct from the way unlawful presence was calculated for other temporary (nonimmigrant) visas (for example, tourist or employment visas). Holders of other visas that have set end dates start accruing unlawful presence the day after they overstay the permitted end date, as usually shown on their I-94 document. This makes sense, because it's clear they are in violation of their visas and have been made aware of when their permitted stay expires.
Being considered "unlawfully present" has extremely negative consequences under U.S. immigration law. People found to have accrued more than 180 days but less than one year, or more than one year of unlawful presence in the U.S., and then who depart the U.S., are barred from returning for three or ten years, respectively.
The new policy put forth by the USCIS memo creates a risk that students and exchange visitors may unwittingly accrue unlawful presence and be barred from returning to the U.S. for years. Under the previous policy, visa holders would have notice that they were beginning to accrue unlawful presence, either due to a determination by an immigration judge or USCIS. They could then react appropriately.
The three- and ten-year unlawful presence bars are triggered only after you leave the United States. For this reason, people with F, J, or M visas must be more cautious about leaving the U.S. after the new memo takes effect (most likely on August 9, 2018).
The new policy is currently open for public comment, however, so it's still possible (but not likely) that it will be rescinded before August 9, 2018. If you have a student or exchange visitor visa in the U.S., be sure to follow developments related to this new policy and take care not to violate any terms of your visa before traveling outside of the United States.