Top Senate Democrats are urging President Joe Biden against reinstating a policy that would detain migrant families who cross the U.S. border illegally.

Bidens administration is reportedly considering reviving the much-criticized policy that Biden himself ended when he took office in 2021. It follows other moves by the administration designed to address the influx of migrants at the U.S.-Mexico border, including barring migrants from applying for asylum in the U.S. if they have traveled through other countries.

Critics of the family detention policy say it would target vulnerable people, including children, and lead to family separations like the thousands of separations that occurred under President Donald Trump .

Under both the Obama and Trump Administrations, family detention had disastrous effects on migrant families and children, without any corresponding improvement in border security or deterrence. We urge you to learn from the mistakes of your predecessors and abandon any plans to implement this failed policy, reads a blistering letter sent to Biden on Monday by 19 Senate Democrats, including Senate Majority Leader Chuck Schumer (N.Y.) and Majority Whip Dick Durbin (Ill.).

The letter was signed by top progressives in the chamber as well as several centrist Democrats, including Tim Kaine of Virginia, who faces reelection next year.

Republicans have hammered Biden over the soaring increase of migrant encounters at the border in recent years, accusing him of failing to do his job. His recent moves cracking down on migrants are seen as an effort to blunt GOP attacks ahead of his expected run for reelection in 2024.

In their letter to Biden, the Democratic senators argued that family detention hasnt worked as intended. Citing data from the Department of Homeland Security, they concluded that the policy does not appear to have deterred desperate families from attempting to come to the United States.

We understand that your Administration faces significant challenges particularly in light of Congressional failure to pass immigration reform to manage an influx of asylum seekers arriving at our southern border, the senators wrote. However, the recent past has taught us that family detention is both morally reprehensible and ineffective as an immigration management tool. We look forward to working closely with your Administration on more thoughtful and humane responses to such challenges.