FIRST ON FOX: The number of illegal immigrants living in the United States increased by approximately a million in the first year of the Biden administration, and cost the American taxpayer an additional $9.4 billion, according to a new analysis by a conservative group.

The study, an early copy of which was obtained by Fox News Digital, was written by the Federation for American Immigration Reform (FAIR) which advocates for lower levels of immigration overall. 

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The study estimates that there are approximately 15.5 million immigrants living in the U.S. illegally, up from 14.5 million in 2020. Other estimates have typically put that number at around 11 million for years, but immigration hawks have expressed skepticism that the number has stayed flat given the increased activity at the border.

FAIR’s analysis also conducted a fiscal cost study, finding that illegal immigrants are imposing a net fiscal burden of at least $143.1 billion – an increase of $9.4 billion over 2020.

The group puts the increase in population down to two factors – the first being the improvement of the U.S. economy as it re-opens after COVID-19.

"Businesses are once again hiring, and many unscrupulous employers are using this as an opportunity to turn to reliably cheap labor to undercut the market and make up for lost profits resulting from economic shutdowns stemming from the pandemic," the report says. "These unethical hiring practices occur even though millions of Americans remain unemployed or underemployed."

border security

June 10, 2021: A pair of migrant families from Brazil pass through a gap in the border wall to reach the United States after crossing from Mexico to Yuma, Ariz., to seek asylum.    ((AP Photo/Eugene Garcia, File))

The second factor is the policies of the administration, which rolled back a number of Trump-era border policies and narrowed the scope of interior enforcement. FAIR claims that Biden "has effectively abolished the mission of U.S. Immigration and Customs Enforcement (ICE), preventing the U.S. Customs and Border Protection (CBP) from securing our southern border, and implementing measures that encourage mass illegal immigration." 

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The report points to the narrowed interior enforcement, the ending of the Migrant Protection Protocols (MPP), ending of border wall construction, continued designations of Temporary Protected Status (TPS) and promising amnesty for illegal immigrants already in the country as part of an immigration reform proposal.

"President Biden and the people he appointed to key positions in his administration have pursued the most radical open-borders policies in the history of any sovereign nation, and these new numbers bear that out," FAIR President Dan Stein said in a statement accompanying the report. "If not for the COVID pandemic, which forced the administration to keep Title 42 in place last year, the additional influx and costs to American taxpayers would have been far greater."

The report says the states with the most illegal immigrants are California (3.3 million), Texas (2.2 million), Florida (1.2 million) and New York (1.1 million.) The states with the fewest illegal immigrants are North Dakota and West Virginia, with 6,000 each.

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It warns, however, that estimating the number of illegal immigrants in the country is always a difficult task.

"[DHS] only (loosely) counts foreign nationals who enter and leave the United States in a lawful manner. In truth, we do not know exactly how many people cross the border unlawfully and evade immigration authorities. We can only estimate these figures based on changes in annual census data, along with how many individuals CBP and ICE believe slip through their detection," it says.

The analysis comes as numbers are again surging at the border to highs not seen in decades, with more than 221,000 migrant encounters in March and that number expected to rise in the months ahead -- both because of the summer months and the planned ending of the Title 42 public health order.

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That order, which has been used by both the Biden and Trump administrations to remove a majority of migrants at the border due to the COVID-19 pandemic, will end on May 23. The administration has said it is planning for potentially up to 18,000 migrant encounters a day.