President Donald Trump used his first primetime address from the White House to call for Democrats to support spending billions to build a wall on the border with Mexico.

With the partial government shutdown now the second-longest in U.S. history, Trump took the unusual step of speaking directly to Americans from the Oval Office Tuesday to press his case. Later in the week, he’ll visit McAllen, Texas as well.

Democratic leaders offered their rebuttal shortly after Trump’s speech.

In recent weeks, Trump and other administration officials have made a number of claims about border crossings and the need for a wall.

Here are the facts behind several of those claims.

Claim: Illegal immigration causes violent crime

“Day after day, precious lives are cut short by those who have violated our borders,” Trump said during his address, noting crimes involving immigrants in recent years. He has repeated this particular claim since he first announced his candidacy in 2015.

Some Americans have allegedly been assaulted, raped and murdered by immigrants who are in the country illegally — including a 33-year-old police officer killed the day after Christmas and a 64-year-old Air Force contractor who was bludgeoned to death with a hammer, as highlighted by Trump. However, studies have shown that immigrants commit crimes less frequently than their American-born counterparts.

According to one published by the CATO Institute in February of 2018, native-born citizens are more likely than immigrants, whether here legally or illegally, to be convicted of a crime. For example, CATO examined 785 Texas homicide convictions in 2015: the conviction rate for illegal immigrants was 16% lower than that of native-born citizens. For legal immigrants, the rate of conviction was 67% lower than that of their native-born counterparts.

Claim: Mexico is paying for the border wall

From the moment that Trump introduced his idea for a border wall in his 2015 campaign announcement, he followed it up with “I will have Mexico pay for that wall.”

On Tuesday night, he repeated the claim — with a slight tweak that he has been using lately: “The wall will always be paid for indirectly by the great new trade deal we have made with Mexico.”

However, experts say that this new claim is problematic in a number of ways.

Expecting the USMCA to pay for the border wall misses the point of the trade agreement, says Welles Orr, who worked on the original NAFTA agreement as the Assistant U.S. Trade Representative for Congressional Affairs under George H.W. Bush.

“Trade agreements are designed to reduce regulatory hurdles,” Orr says. “Most of our tariffs are zero, or very, very low.”

Orr says that he likes the trade agreement because it adds new provisions to the NAFTA agreement — such as addressing e-commerce — and says it’s not necessarily adding new tariffs.

And even if it did add new tariffs, Orr added, they won’t go directly to a wall or other project. Any funds collected through a tariff would go into the U.S. Treasury fund — not to a particular project, Orr says.

“That’s not the way trade agreements work,” Orr says. “Tariffs that are collected by the U.S. Treasury would fund the U.S. Treasury.”

Orr also notes that the trade agreement hasn’t been ratified by the U.S., Mexico and Canada yet, and won’t be until “spring at the earliest.”

The final agreement still needs to be formally ratified by the United States, Mexico and Canada — including by the now Democrat-controlled House. Passage may be months away.

Both the new Mexican president, Andrés Manuel López Obrador, and his predecessor are strongly against the border wall — and the political situation in Mexico makes it very unlikely that the country would fund such a wall, says Juan Carlos Hartasánchez, a trade analyst who has worked with Mexican banks and companies.

“From my position, it’s a stretch to say the USMCA in any way would be able to fund a border wall,” Hartasánchez says.

Like the preexisting NAFTA agreement, USMCA includes portions that would benefit all three countries. The one element that could be said to advantage American manufacturers is the auto parts segment, which would increase the ratio of parts in a car that need to be built in the United States, Hartasánchez says.

However, Hartasánchez argues that it’s unclear how much Mexican manufacturers would actually be paying. Manufacturers would typically work to avoid such a tariff by adjusting their supply lines — and might pass the cost of a tariff off to consumers.

“It’s unclear who would pay for it. It might be the American taxpayer, who is paying for a more expensive product,” says Hartasánchez.

Claim: A border wall will stop the flow of drugs into the U.S.

“Our southern border is a pipeline for vast quantities of illegal drugs, including meth, heroin, cocaine and fentanyl,” Trump said Tuesday. “Every week 300 of our citizens are killed by heroin alone, 90% of which floods across from our southern border. More Americans will die from drugs this year than were killed in the entire Vietnam War.”

Trump’s assertion that 90% of heroin comes from the southern border appears to be accurate. Then-Assistant Secretary of International Narcotics and Law Enforcement Affairs William Brownfield told reporters in 2017 that 90 to 94% of heroin consumed in the United States today comes from Mexico.

However, the vast majority of heroin that crosses over from Mexico is smuggled through legal ports of entry – not in the vacant parts of the border that the wall would occupy, according to the U.S. Drug Enforcement Agency’s (DEA) 2018 National Drug Threat Assessment.

“A small percentage of all heroin seized by [Customs and Border Protection agents] along the land border was between Ports of Entry,” the DEA wrote.

“The majority of the [heroin] flow is through [private vehicles] entering the United States at legal ports of entry, followed by tractor-trailers, where the heroin is co-mingled with legal goods.”

Claim: ‘Much of the wall’ has already been built

Ten days into the shutdown, Trump tweeted that America should finish building a wall at the U.S.-Mexico border because much of the wall is already complete. On another occasion, Trump told reporters in the Rose Garden that “we just finished brand-new walls” in San Diego and other parts of California.

While there are some barrier structures along the southern border, no new structures have been built since Trump took office. The “brand-new walls” in California Trump was referencing were merely renovations of existing infrastructure. Furthermore, while the southern border is nearly 2,000 miles long, current structures line only 654 miles of the border, according to the U.S. Government Accountability Office. During his 2016 campaign, Trump indicated he wanted the wall to line 1,000 miles of it.

Claim: ‘Nearly 4,000 known or suspected terrorists’ tried to cross the Southern border

At a Rose Garden press conference on Friday, Trump said terrorists come to the United States by way of the southern border because it’s the easiest place to enter. “We have terrorists coming through the southern border because they find that’s probably the easiest place to come through,” he told reporters.

Over the course of the last week, both White House Press Secretary Sarah Huckabee Sanders and Vice President Mike Pence claimed nearly 4,000 known or suspected terrorists were found trying to enter the United States. Sanders even said the southern border was the “most vulnerable point of entry.”

Both of these claims are misleading at best. NBC reported Monday that only six immigrants whose names were on a federal watch list of known or suspected terrorists were found by Customs and Border Protection agents at ports of entry along the U.S.-Mexico border in the first half of fiscal year 2018, according to CBP data provided to Congress in May.

Additionally, the Department of Homeland Security asserts it stopped approximately 3,700 individuals on the terrorist watch list from entering the United States in fiscal year 2017, but that represents all people on the watch list trying to enter illegally, not just ones who came by way of the U.S-Mexico border. The department itself also notes the southern border is not the typical path of entry.

“Most of these individuals are trying to enter the U.S. by air,” a DHS fact-sheet reads.

Another figure that has been used to discuss border crossings is the number of “special-interest aliens” trying to enter along the southern border. The Department of Homeland Security asserts more than 3,000 of these individuals were stopped in the area last year, but a former immigration official tells TIME the term is not at all synonymous with “suspected terrorist.”

Theresa Cardinal Brown, who used to work for both Customs and Border Protection and Homeland Security says “special-interest alien” is a term that “has not been officially defined by the government, but as usually used, is meant to mean people that are selected for additional scrutiny because they are either from a country that is known to have terrorist activity in the country or terrorist sponsors.” It can also be used to refer to people who have merely traveled to or from some of those countries, she says.

Claim: Democrats spiked an earlier immigration compromise

On Dec. 27, 2018, Trump claimed the Democrats and the courts “obstructed” a deal that would have traded reform of the Deferred Action for Childhood Arrivals program (DACA) in exchange for border wall funding.

But that’s not a fair representation of what happened, according to experts. Trump ended the DACA program, which allowed some children who were brought to the United States illegally as children to delay deportations and become eligible for work, in September 2017. He gave Congress a six-month window to create a legislative fix for the program that was appealing to both sides.

Last year, the White House and Democrats had discussed a compromise in which Trump would get funding for border security and DACA would be saved. But in Jan. 2018, a federal judge issued an injunction mandating DACA resumes until the Supreme Court can consider the case.

Raul Hinojosa-Ojeda, a UCLA professor with expertise in immigration says “there was no reason why he couldn’t cut a deal” in light of the injunction.

“In fact, that’s exactly what the Supreme Court is probably going to end up saying, that this is something that should be handled by the legislature,” Hinojosa-Ojeda said. “It wasn’t the Democratic Party who brought this case up in front of the 9th Circuit.”

But regardless of the misleading numbers and allegations of blame, this shutdown fight is about a wall that some argue wouldn’t work in the first place.

“I think the piece that’s missing from a lot of this,” Brown says “is that the administration is trying to make the case that there’s a crisis at the U.S.-Mexico border based on all these facts. What they have not documented is how the building of a border wall will actually address those problems.”

Claim: There’s a crisis on the border because of a historically high rate of crossings

Trump and members of the Administration, including Pence and Homeland Security Secretary Kirstjen Nielsen, have repeatedly referred to the situation at the border as a “crisis.”

Last June, Nielsen compared the current situation at the border to 2017 in a press briefing, noting that the current flow of migrants is “multiples” beyond last year.

“In the last three months, we have seen illegal immigration on our southern border exceed 50,000 people each month,” Nielsen said.

More people were, in fact, apprehended at the Southwest border in 2018 compared to the previous year. According to U.S. Customs and Border Protection data, more than 521,000 people were apprehended in compared to 416,000 in 2017 – a 23% increase.

However, this number pales in comparison to apprehensions in the George W. Bush Administration – especially 2005 and 2006 when more than 1 million migrants were stopped each year.

At that time, even more migrants were probably crossing than authorities realized. That’s because most Central Americans who make the dangerous trek to the United States these days want to get caught, says Randy Capps, the director of research for U.S. programs for the Migration Policy Institute.

In the early 2000s, most migrants were Mexican men coming to the U.S. to find higher paying jobs. Today, most migrants at the southern border intend to turn themselves in and apply for asylum in the United States.

“Back in those days, more people probably got past the border security than got apprehended,” Capps says. “We don’t have that kind of a crisis right now.”

In 2005, 86% of the apprehended migrants were from Mexico; 82% were male, and only 18% of the migrants were under the age of 17, according to U.S. Customs and Border Protection. By 2017, only 42% of the migrants apprehended were from Mexico, with the majority of the others coming from Central America, and more than 107,000 “family units” were apprehended.

Additionally, the wall would do nothing to stop the number one source of illegal immigration to the United States, Capps says. More than 700,000 people overstayed their visas in the United States in 2017, according to the Department of Homeland Security.

A wall would also fail to stop the flow of drug trafficking, which is increasingly coming through legal ports of entry. The most common mode of transport is inside passenger vehicles and trucks, according to the Drug Enforcement Administration.

The wall, Capps says, “is a solution to a 10-year-old problem.”

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Write to Abby Vesoulis at abby.vesoulis@time.com and Gina Martinez at gina.martinez@time.com.