In a long-awaited memo, Homeland Security Secretary Alejandro Mayorkas outlined a dramatic shift in U.S. immigration enforcement policy that will likely spare most undocumented immigrants who have lived in the U.S. for years from arrest and deportation, as long as they don’t commit serious crimes. “The majority of undocumented non-citizens who could be subject to removal, the majority of the more than 11 million people, have been contributing members of our communities for years,” Mayorkas told reporters. “They include individuals who work on the frontlines in the battle against COVID, teachers, individuals who teach our children, who do the back-breaking farmwork that puts food on our table, who lead our congregations of faith and contribute to our communities in meaningful other ways.” Mayorkas’ guidelines will supersede a similar February memo that also narrowed who U.S. Immigration and Customs Enforcement (ICE) agents should prioritize for deportation. In August, a federal judge in Texas blocked those rules, arguing that they were improperly enacted and led U.S. officials to violate federal immigration laws. An appeals court later paused the judge’s order. Thursday’s guidelines, which are set to take effect in 60 days, go further in limiting immigration arrests than the Obama-era immigration enforcement priorities, which were scrapped by Trump administration officials, who argued that all unauthorized immigrants should be subject to deportation. Like the February ICE rules, Mayorkas’ department-wide memo instructs officials to prioritize the arrest of immigrants deemed to pose a national security threat, like those accused of terrorism or espionage. Migrants who crossed the U.S.-Mexico border without permission after November 1, 2021 are also a priority for deportation. The biggest shift from the February rules is the new “public safety” threat category, which currently directs deportation agents to seek the arrest of immigrants convicted of an “aggravated felony,” as defined by U.S. immigration laws, or those accused of participating in a criminal gang. The new rules define a public safety risk as someone who has engaged in “serious criminal conduct” and direct agents to look at “the totality of facts and circumstances.” U.S. immigration officials are instructed to consider the gravity of the offense, the degree of harm inflicted on victims, the sophistication of the crime and the use of firearms or weapons, as well as mitigating factors, like the potential advanced or tender age of the immigrant, the time he or she has lived in the U.S., military service and eligibility for humanitarian relief. “To treat people and questions of public safety threat categorically like that actually is not effective [and] could lead to infective and unjust results,” Mayorkas told reporters Thursday. Thursday’s memo is part of a broader Biden administration effort to restrict immigration arrests and deportations from the interior of the country. ICE officers have also been instructed to generally avoid detaining pregnant or nursing women, victims of serious crimes and immigrants attending court appointments. The Biden administration has argued that the restrictions on ICE arrests allow the agency to focus its limited resources on detaining noncitizens with serious criminal convictions, while sparing undocumented immigrants without criminal records who have lived in the U.S. for years. But Republicans have suggested that the policy changes encourage migrants to come to the U.S. and stay in the country illegally.