Flores was implemented in 1997 during the Clinton administration as an agreement with immigration activists.
California District judge Gee rules that the Flores Agreement applies to both unaccompanied minors and accompanied minors and that the minors must be turned over to DHS within the U.S. within 20 days. This means that minors had to be released while the parents or guardians were still being held pending hearing.
It is this ruling that led to what is known as "family separation". This loophole led to the increase in asylum claims by families. Now, any adult with a child could come to the border, surrender, claim fear and know that they will be released into the U.S. in 20 days. ref
, pdf of ruling
Catch and release loophole begins
Ninth Circuit reaffirmed that decision. ref
Trump implements "Zero Tolerance" in an effort to protect the Southwest border. The Justice Department then prosecuted every illegal border crossing with the crime of entry without inspection. Trespassers faced about 6 months in prison for the 1st offence and up to 2 years the second offence. video ref
Due to the expansion of the Flores Agreement by activist judges, children and families were required to be separated and released into the U.S. or released into the U.S. with their parents after 20 days and hope that they show up in court later to process their asylum claims.
Trump signs executive order to detain families together. ref
Acting Homeland Security Secretary Kevin McAleenan announces the end to "Catch and Release" saying that family units would be released back to their country of origin if there was no claim of fear of return or to Mexico if there was a claim of fear of return, but they would no longer be released into the U.S. ref
Catch and release loophole ends