In 1997, the U.S. Department of Justice agreed to a settlement in a case called Flores vs. Reno. Among other things, this settlement prohibits unaccompanied children who have crossed the border from being held in federal detention facilities for longer than 20 days. In 2016, the Ninth Circuit Court of Appeals ruled that this 20 day prohibition applies to both accompanied minors (children who came along with family members) and unaccompanied minors.
This has all become relevant now because of the Trump Administration's new "zero tolerance" policy and the family separations that have resulted from it. Many Republicans, including Trump Administration officials, have argued that separating families is necessary because if a parent requests asylum, it usually takes longer than 20 days, so under the Flores settlement either the government has to let both the parent and child go after 20 days (which Republicans deride as "catch and release"), or detain the parent and release the child in which case they're separated. So they're demanding that legislation be passed overturning the Flores settlement and allowing the government to detain parents and children together for longer than 20 days (and demanding various border security measures in return).
Now this is a bit of a red herring, because the "zero tolerance" policy would separate families with or without the Flores settlement. But my question is, does the Trump Administration have the power to undo the Flores settlement on its own? Can the Executive branch break court settlements it's entered into, or does it require legislation to break a court settlement?