Washington (CNN) The topic of immigration has been one of the most controversial during this presidential election. Republican nominee, Donald Trump has made many claims about the issue. CNN's Reality Check Team put his statements and assertions to the test.

The team of reporters, researchers and editors across CNN listened throughout the speeches and selected key statements, rating them true; mostly true; true, but misleading; false; or it's complicated.

Reality Check: Trump on undocumented immigrants with criminal records

July 21, 2016

By Lisa Rose, CNN

At the final night of the GOP convention, Trump returned to a familiar theme in his speech, warning that dangerous criminals from Central and South America have entered the United States illegally and are at large.

"Nearly 180,000 illegal immigrants with criminal records, ordered deported from our country, are tonight roaming free to threaten peaceful citizens," said Trump.

Trump likely got that number from a congressional hearing last December, when Iowa Republican Sen. Chuck Grassley said that there were 179,027 undocumented criminals awaiting removal and at large. Although the statistic is more than six months old and we can't confirm exactly how many of those criminals have been deported, we rate Trump's claim as true.

Trump then conflated criminals with families apprehended at the border.

"The number of new illegal immigrant families who have crossed the border so far this year already exceeds the entire total from 2015," Trump said. "They are being released by the tens of thousands into our communities with no regard for the impact on public safety or resources."

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According to the Department of Homeland Security, the number of apprehensions of families on the southwest border has spiked in 2016 but there is no indication that the families are being released en masse. Therefore, our verdict on this claim is true, but misleading.

And then the real estate mogul said in conclusion:

"One such border crosser was released and made his way to Nebraska," said Trump. "There, he ended the life of an innocent young girl named Sarah Root."

Trump was referring to a man from Honduras, Eswin Mejia, who killed Root last January in a drunk driving accident. The incident was a tragedy -- Root had graduated from college hours before the wreck with a 4.0 grade point average -- but Trump's description of the undocumented immigrant's background had inaccuracies. Mejia did not recently arrive in America, as Trump suggested -- he has been here since at least 2013. And Mejia did not have a criminal record in Honduras, according to Immigration and Customs Enforcement. These claims are false.

Reality Check: Trump says Clinton money for refugees could rebuild every inner city in America

June 22, 2016

By Sonam Vashi and John Newsome, CNN

During a 40-minute speech in New York, Trump said, "Hillary also wants to spend hundreds of billions to resettle Middle Eastern refugees in the United States, on top of the current record level of immigration. For the amount of money Hillary Clinton would like to spend on refugees, we could rebuild every inner city in America."

First: how much do we spend on refugees, and how much more does Clinton want to spend?

In fiscal year 2015, the Office of Refugee Resettlement (ORR), which is under the Department of Health and Human Services, had about 1.6 billion to spend on services such as medical assistance, employment services, and English language training, among others.

More than half of the ORR's budget, or about $950 million, goes to temporary custody and care of tens of thousands of unaccompanied children, who are almost all from Central America and Mexico

In fiscal year 2015, the State Department spent about $3 billion on Migration and Refugee Assistance, and it spent $50 million on Emergency Refugee and Migration Assistance.

On CBS News' "Face the Nation" last September, Clinton was asked if the current U.S. plan to increase the number of admitted Syrian refugees to 10,000 was enough. She replied, "I would like to see us move from what is a good start with 10,000 to 65,000 and begin immediately to put into place the mechanisms for vetting the people that we would take in."

There's no clean or accurate way to estimate how much each refugee costs the U.S. For an overly simplistic estimate: if we look at the part of ORR's budget that is not dedicated to the custody of Central American children (about $611 million in FY2015), the total number of refugees admitted (about 70,000), and then add in the 55,000 more Syrian refugees Clinton is proposing, the cost to the U.S. government might look something closer to $1.1 billion per year (about $500 million more than what ORR spends now), plus the $3 billion per year from the State Department.

That $4.1 billion doesn't include resettlement services funded by the private sector; NGOs like the International Rescue Committee , which helps resettle refugees in the U.S., are heavily funded by private donations. It also doesn't include the positive economic impact refugees have on their communities once resettled, according to studies.

Meanwhile, the amount of money required, both from public and private sources, to revitalize all of America's inner-cities is so massive it is hard to quantify.

The Initiative for a Competitive Inner City organization, a Boston-based incubator and accelerator for inner-city growth, calls such an undertaking enormous.

"We cannot put a price tag on the vast long-term public and private investment required to revitalize America's inner cities. We know that there are at least 328 inner cities in the United States with high levels of poverty and unemployment. They demand enormous public and private resources to deal with the profound challenge of economic inequality that plagues our cities," the group's CEO, Steve Grossman, tells CNN.

Given how massive the price tag would be to revitalize all of America's inner cities, it's clear that it would be much larger than the approximate $4.1 billion per year that the U.S. spends on refugees.

Verdict: False.

Reality Check: Trump on 'Operation Wetback'

November 10, 2015

By Sonam Vashi, CNN

Billionaire Donald Trump claimed Dwight Eisenhower successfully deported 1.5 million immigrants after sending them deep across the border.

During the GOP debate in Milwaukee, Trump said, "Dwight Eisenhower ... moved a million and a half illegal immigrants out of this country, moved them just beyond the border. They came back. Moved them again, beyond the border. They came back. Didn't like it. Moved them way south. They never came back."

Eisenhower's policy, named "Operation Wetback," was implemented in 1954 and deported undocumented immigrants deep into Mexico. Many of the undocumented had come through wartime Bracero programs, when American labor needs led to a policy that allowed Mexicans to come to the U.S. for temporary agricultural work. When the temporary contracts were not renewed, many workers became illegal.

The exact number that the operation deported is unclear. Eisenhower's attorney general, Herbert Brownell, Jr., said in 1955 that the operation had deported 1 million people, but other researchers put that number closer to 250,000. Between 1953 and 1955, the U.S. Immigration and Naturalization Service recorded more than 800,000 apprehensions, according to Mae M. Ngai's "Impossible Subjects: Illegal Aliens and the Making of Modern America." Some research shows that more Mexicans may have left the U.S. voluntarily due to fears of apprehension.

However, Trump never mentioned the inhumane practices that occurred when the INS deported the workers back into Mexico in the 1950s. The transfer process was widely criticized as inhumane. Some deportees were transported in over packed trucks or were dropped off without resources in the desert and died from heat stroke; others drowned after transport on overloaded ships, according to Ngai's book.

Verdict: True, but misleading

Fact check: Donald Trump says Mexico sends its criminals across the border.

August 6, 2015

Trump said that Mexico sends its criminals across the border while the U.S. does nothing.

"They send the bad ones over because the stupid leaders of the United States will take care of them and that's what's happening, whether you like it or not," he said.

But the Pew Center shows that the number of undocumented immigrants coming from Mexico has actually declined after the recession of 2008 and the undocumented population is stable at 11 million people.

The Pew report also notes that the deportations hit a record high in 2013, around 400,000 per year, and many were criminals.

We find Trump's claim to be False.