Much of this time line comes from here.

2017: In El Paso, adults who crossed the border without permission – a misdemeanor for a first-time offender – are detained and criminally charged. No exceptions are made for parents arriving with young children. The children were taken from them, and parents were unable to track or reunite with their children because the government failed to create a system to facilitate reunification. By late 2017, the government was separating families along the length of the U.S.-Mexico border, including families arriving through official ports of entry.

May 7, 2018: the U.S. Department of Justice (DOJ) announces it had implemented a “zero tolerance” policy, dictating that all migrants who cross the border without permission, including those seeking asylum, be referred to the DOJ for prosecution. Undocumented asylum seekers were imprisoned, and any accompanying children under the age of 18 were handed over to the U.S. Department of Health and Human Services (HHS), which scattered them among 100 Office of Refugee Resettlement (ORR) shelters and other care arrangements across the country.

June 15, 2018: For the first time, DHS publicly acknowledges that it separated nearly 2,000 children from their parents or legal guardians between April 19 and May 31. The government’s protocol for reunifying families has yet to be made clear.

June 17, 2018: Homeland Security Secretary Kirstjen Nielsen tweets, falsely: “We do not have a policy of separating families at the border. Period.”

June 18 2018: Tweet by Stephen Miller: “It was a simple decision by the administration to have a zero tolerance policy for illegal entry.” 

June 20, 2018: Reacting to mounting public pressure, President Trump signs an executive order directing DHS to stop separating families except in cases where there is concern that the parent represents a risk to the child. Trump falsely blames Congress, the courts and previous administrations for his family separation policy.

June 26, 2018: U.S. District Judge Dana Sabraw issues a preliminary injunction requiring U.S. immigration authorities to reunite most separated families within 30 days and to reunite children younger than 5 within two weeks.

Oct. 15, 2018: The government reports to a court that a total of 2,654 children have been separated from their parents, and of that number, 2,363 have been discharged from custody. 125 children made the decision to pursue asylum in the U.S. without their parent.

Jan. 17, 2019: The list of families to be reunified is “still being revised” nearly six months after reunification is ordered by a federal court,

April 6, 2019: The government says in court documents that it may take two years to identify potentially thousands of children who’ve been separated from their families at the southern border.

Aug. 21, 2019: DHS and the U.S. Department of Health and Human Services (HHS) announce a new rule that would end the Flores settlement, a consent decree in place for more than two decades that limits the length of time migrant children can be detained by U.S. Customs and Border Protection to 20 days, requires the government to comply with certain standards of care, and states that children must be placed in the “least restrictive” setting appropriate for their age and needs. The Trump administration’s rule would allow it to indefinitely detain migrant families who crossed the border without authorization.

Sept. 27, 2019: U.S. District Judge Dolly Gee of the Central District of California rejects the administration’s plan to end the Flores settlement.

October 3, 2019: The American Civil Liberties Union and partners file a federal lawsuit (A.I.I.L. v. Sessions) seeking damages on behalf of thousands of traumatized children and parents who were forcibly torn from each other under the Trump administration’s practice of separating families at the border.

February 2, 2021: President Biden signs executive order 14011 to establish the interagency task force on the reunification of families.

June 8, 2021: The task forces counts 3,913 children of having been separated. Of the 3,913 children, 1,786 have been reunified with a parent, mostly during Trump’s tenure, parents of another 1,965 have been contacted and the whereabouts of 391 have not been established. Many who have been contacted were released to other family members.

Sept 30, 2021: The task force issues an interim report: As of September 23, the task force has identified 3948 children who were separated from their parents by the department of Homeland Security at the United States Mexican border between July 1, 2017 and January 20, 2021. The task force is aware of 410 children who were returned to the home country, some with in some without their parents, and 1,707 parents who were returned to their home country, some with and some without their children. The task force confirm that 2171 children have been reunified with the parents in the United States; in addition, the task force has reunified 50 children. There are 1,727 children who have not been reunified to the task force’s knowledge and 50 children who are in the process of being unified by the task force.

December 16, 2021: The Biden administration abandons negotiations over compensation for plaintiffs in ACLU class action suit filed October 3, 2019.