President Donald Trump continues to falsely blame Democrats for an administration policy that has led to more than 2,000 children being separated from their parents at the U.S. border.

Speaking at a White House event on space Monday morning, Trump again said that the policy is “the Democrats’ fault” because they will not work with Republicans to revise immigration laws.

The family separations began earlier this year after Attorney General Jeff Sessions announced a new “zero tolerance” policy of referring all border crossings for federal criminal prosecution, which leads to children being separated as their parents are sent to jail.

“If the Democrats would sit down instead of obstructing, we could have something done very quickly — good of the children, good for the country, good for the world,” he said. “We have the worst immigration laws in the entire world. Nobody has such sad, such bad … and actually in many cases, such horrible and tough. You see about child separation, you see what’s going on there.”

That echoed remarks from Friday, when Trump also blamed his own administration’s policy on Democrats, who are in the minority in both chambers of Congress. “I hate the children being taken away,” he told reporters at the White House. “The Democrats have to change their law — that’s their law.”

Here’s a closer look at the facts behind the family separation policy.

What is the family separation policy?

In May, Sessions announced that the U.S. would take a stricter stance on illegal crossings at the Mexican border which would result in parents and children being separated, rather than keeping them together in detention centers.

“If you are smuggling a child then we will prosecute you, and that child will be separated from you as required by law,” Sessions said at a law enforcement event in Scottsdale, Ariz. “If you don’t like that, then don’t smuggle children over our border.”

From April 19 to May 31, some 1,995 children were separated from roughly as many adults at the U.S. border, officials announced on Friday.

The children are being held in facilities run by the Office of Refugee Resettlement within the Department of Health and Human Services, such as a converted Walmart in Texas which houses young boys that was recently opened to reporters.

While the the Trump Administration has released photos of young boys being held at detention centers, it so far has not released any images of young girls. Migrant rights groups told TIME they are concerned about the risks that girls and young women face in the facilities, citing issues such as pregnancy and psychological trauma from assault and rape they faced in their home countries.

Especially young children, such as toddlers, are being sent to “tender age” shelters in South Texas. At least one of the makeshift facilities was previously a warehouse. A New York TV station reported that some children were being taken to a foster agency in East Harlem.

What has the White House said about the family separation policy?

The Trump Administration has sent mixed messages about the policy. While Trump has repeatedly — and falsely — blamed Democrats for the policy, other staffers have either denied there is a policy or argued that it is a positive.

On Friday, Trump tweeted that “the Democrats are forcing the breakup of families at the Border with their horrible and cruel legislative agenda.”

Meantime, White House senior policy adviser Stephen Miller defended the policy, arguing that it shows that no one is above the law.

“It was a simple decision by the administration to have a zero tolerance policy for illegal entry, period,” he told the New York Times. “The message is that no one is exempt from immigration law.”

At the same time, Homeland Security Secretary Kirstjen Nielsen tweeted on Sunday that there was no family separation policy. “We do not have a policy of separating families at the border. Period,” she wrote. Instead, she argued that it was a continuation of previous administrations’ policies of separating children if “the adult has broken a law.”

But on Monday, Nielsen defended the policy while speaking before the National Sheriffs’ Association and suggested that people were “fraudulently” using children in order to pose as families and cross the border.

“Illegal actions have and must have consequences,” she said. “No more free passes, no more get out of jail free cards.”

How have past presidents handled families that crossed the border?

The Trump Administration is not the first to face surges in migrants crossing the border nor is his the first to have to address the issue what to do about of families crossing the border. The Bush Administration aggressively pursued prosecutions of illegal entrants under a similarly “zero tolerance” policy in response to upticks.

A Bush-era inspector general report from the Department of Homeland Security found that family separations happened when a parent is criminally charged or if family shelters and facilities lacked space. And according to the Bipartisan Policy Center, in response to Congressional pressure over the separations, the Department opened a family detention center in Texas to expand its capacity only to face more backlash due to the fact that the facility was a former medium-security prison.

The Obama Administration dealt with a major surge in migrants and primarily detained families together in administrative facilities or released them, according to the Migration Policy Institute. It also faced fierce backlash over its family detention policy, including from Congressional Democrats and advocates who criticized officials who said detentions could serve as a deterrent, and faced a number of legal challenges over it.

What does the law say about family separation?

There are laws and court precedent governing how children are treated at the border, however, but none mandates the separation of parents and children. Under a 1997 legal agreement known as the Flores Settlement, there are limits on how long children can be detained and requirements that the government releases them to parents, guardians, or licensed facilities as quickly as possible and houses them in the “least restrictive” setting possible if that cannot happen immediately.

The law that established the Department of Homeland Security, the Homeland Security Act of 2002, also addressed the fate of unaccompanied minors by establishing the Office of Refugee Resettlement, which oversees the care of unaccompanied kids. That office adheres to standards outlined by the Flores Settlement and anti-trafficking laws that also govern how children in U.S. custody are cared for, including screening to determine which placement facility would be deemed the “least restrictive” depending on any particular needs they might have.

In fact, the Office of Refugee Resettlement’s website states that “under most circumstances, ORR places siblings together and unaccompanied alien children who are parents with their children,” although there are instances when that does not happen.

Under a 2008 anti-human trafficking law, which was signed into law by President George W. Bush, federal official are required to screen unaccompanied minors for trafficking and in most cases, refer them to ORR at least 72 hours after they are determined to be alone. Most are guaranteed an immigration hearing.

That law has come under fire during previous surges of unaccompanied minors crossing the border because children who are nationals of “contiguous countries,” like Mexico, can be quickly returned to their home countries once federal officials determine they are not a victim of or at risk for human trafficking if they go home and that they do not have a “credible fear” of persecution, or a solid case for asylum. Children from other countries, however, are not immediately returned and thus trickle through the backlogged immigration court system.

Trump Administration officials have often characterized these policies as “loopholes” that are exploited by those seeking to enter the U.S. Some administration officials have suggested that the “zero tolerance” policy could serve as a deterrent for other migrants who are seeking to come to the U.S.

So far, that hasn’t been the case. Data obtained by CNN show the exact opposite: the number of people caught illegally crossing the border has increased approximately 5% when compared to figures from April. This statistic includes a substantial increase in unaccompanied children.

What will happen next with the family separation policy?

President Trump has suggested that the policy could be revoked if Congress passes an immigration bill. The House of Representatives is set to vote on legislation this week: a hardline bill that limits some forms of immigration as well as a moderate bill that could address the issue of family separations.

According to polls, the majority of Americans are against the policy, but Republicans are much more supportive.

A recent Quinnipiac University poll found that 66% of Americans are opposed to the policy and 27% support it. But some 55% of Republicans are in favor of the policy and 35% oppose it.

A Daily Beast/Ipsos poll of 1,000 people found that 56% of respondents thought it was not appropriate to separate families in order to discourage others from crossing the border and 27% thought it was OK. About 46% of Republicans in that survey said it is appropriate.

Correction: The original version of this story misstated the percentage of Americans in support of the zero tolerance policy that has resulted in family separations, according to a recent Quinnipiac University poll. Twenty-seven percent of respondents support it, while 66% oppose it.

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