Trump's joint address guests include relatives of people killed by undocumented immigrants

— -- President Donald Trump and first lady Melania Trump will invite three relatives of victims of deadly crimes committed by undocumented immigrants to the president's joint address before Congress on Tuesday.

The White House guest list includes Jessica Davis and Susan Oliver, widows of California police officers killed in the line of duty by a person living in the country illegally, and Jamiel Shaw Sr., whose son was shot by an undocumented immigrant.

The guests highlight the president's focus on crimes allegedly committed by immigrants in his push for tighter immigration controls.

Kicking off his presidential campaign back in 2015, Trump created a controversy when he said immigrants from Mexico was were "bringing crime" and "they’re rapists."

Shortly after taking office, Trump issued an executive order directing the Department of Homeland Security to publish weekly lists of “criminal actions committed by aliens and any jurisdiction that ignored or otherwise failed to honor any detainers with respect to such aliens.”

But a number of scientific studies conducted over the past several years contradict the idea that immigrants are responsible for a disproportionate share of crime.

The research concludes that immigrants are not more likely than U.S.-born individuals to take part in crime, Christopher P. Salas-Wright, an assistant professor at Boston University’s School of Social Work, told Politifact in 2016. "Again and again, we see evidence that they are not," Salas-Wright said. "In fact, it’s the opposite."

A 2016 study published in the Journal of Quantitative Criminology actually suggests that communities that recorded significant increases in immigration had a sharper reduction in crime compared to areas that had less immigration.

The Cato Institute, a libertarian think tank, called the research on immigrants and crime "fairly one-sided," noting that "with few exceptions, immigrants are less crime prone than natives or have no effect on crime rates."

ABC News' Jim Avila and Alisa Wiersema contributed to this report.