Three months ago, he re-opened Matter of A-B (named for the woman's initials) - which affirmed the asylum status of a woman from El Salvador who was the victim of domestic violence - to make his announcement, as the case went to the Board of Immigration Appeals.
The government does not say how many asylum claims are for domestic or gang violence, but asylum seeker advocates said there could be tens of thousands of domestic violence cases in the current immigration court backlog.
"You have a woman who barely survived more than a decade of horrific violence, who finally feels that she secured safety ... and now she's thrown into total turmoil again", said Musalo, who directs the Center for Gender and Refugee Studies at the University of California Hastings' law school.
Fifteen former immigration judges signed a letter calling Mr Sessions' decision "an affront to the rule of law". That last category often included domestic violence victims and victims of gang violence.
The woman could still potentially appeal the case again to the Board of Immigration Appeals, then a federal appeals court and ultimately the U.S. Supreme Court.
They estimated that tens of thousands of asylum seekers would be shut out of the United States as a result.
Fox News host apologizes for calling Kim Jong Un, Trump 'two dictators'
The anchor apologised later in the show. "I did not mean that my mistake, so I apologise for that." said Abby. She also tweeted a second apology in the afternoon, "I'll never claim to be a flawless human being".
Domestic violence is a "particularly hard crime to prevent and prosecute, even in the United States", Mr Sessions wrote, adding that its prevalence in El Salvador does not mean that its government was unwilling or unable to protect victims any less so than the United States. Asylum-seekers must also demonstrate that their home government is unwilling or unable to protect them.
The attorney general did not reveal the specifics of the changes to the law. Despite President Donald Trump's tough talk on immigration, border arrests topped 50,000 for a third straight month in May and lines of asylum seekers have grown at USA crossings with Mexico.
In May, Sessions announced a stricter position on separating parents and children who attempt to cross the border illegally, in part to discourage people from attempting to seek asylum, according to Gilman.
The Trump administration has accused migrants of exploiting the asylum system to gain entry to the United States, aware that the immigration courts are so backlogged that their cases could take years to complete.
A Charlotte, North Carolina-based immigration judge denied the woman asylum.
In a speech earlier that day, the Times reported that Sessions bolstered this ruling by saying "asylum was never meant to alleviate all problems-even all serious problems-that people face every day all over the world".