Washington (CNN) President Donald Trump used Tuesday's joint address to Congress to call attention to crimes committed by undocumented immigrants, inviting guests affected by such crimes and describing a new office he has ordered created to report them.

As mandated by Trump's executive order signed last month, the Department of Homeland Security announced in implementation guidance issued last week that it would create the Victims Of Immigration Crime Engagement office, or VOICE.

"I have ordered the Department of Homeland Security to create an office to serve American victims," Trump said Tuesday night. "We are providing a voice to those who have been ignored by our media, and silenced by special interests."

What did Trump order?

In establishing the office as called for in Trump's January 25 executive order, DHS Secretary John Kelly ordered the reallocation of any department resources currently going to advocating for undocumented immigrants that can be re-routed to fund the office.

VOICE's job will be to work with victims of crimes committed by undocumented immigrants.

Trump called in his order for the office to issue reports once a quarter "studying the effects of the victimization by criminal aliens present in the United States."

How did he make his case?

Trump invited three guests whose family members were allegedly killed by criminals living in the US illegally, acknowledging them individually as he described his recent crime reporting initiative.

To make his point, Trump in his speech recognized Jamiel Shaw, Susan Oliver, her daughter, Jenna Oliver, and Jessica Davis.

Shaw's teen son, Jamiel Shaw Jr., was murdered by a gang member living in the US illegally.

Susan Oliver and Davis' husbands were Deputy Sheriff Danny Oliver and Detective Michael Davis, who were killed in the line of duty in California. An undocumented immigrant is charged with their murders.

"To Jamiel, Jenna, Susan and Jessica: I want you to know -- we will never stop fighting for justice," Trump said. "Your loved ones will never be forgotten, we will always honor their memory."

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Why is it controversial?

The line about creating VOICE in Trump's speech elicited some audible groans from Democrats in the chamber.

Along with a similar provision in the executive order requiring weekly reports about crimes committed by undocumented immigrants designed to name and shame sanctuary cities, critics fear the measures are designed to skew public opinion unfavorably toward immigrants. Studies conducted by organizations that support pro-immigration policies have found that immigrants commit crimes at a lower rate than the general public, findings that supporters of hardline immigration policies say don't matter.

"The point is that every crime that is committed by someone who is here illegally is a crime that would not occur if they weren't in the country," said Hans von Spakovsky, a legal expert at the conservative Heritage Foundation.

Illinois Democratic Sen. Tammy Duckworth, on the other hand, called the initiative "horrifying" and said Trump was exploiting his guests.

"Especially this VOICE program, I find horrifying," Duckworth told CNN. "And for him to bring guests who suffered such tragedies, but to use it as a political point when it comes to undocumented immigrants, is sad. I wish he would have -- he touched on DREAMers a little bit -- but really no real discussion about he was going to go about doing this other than build more walls."

Latino Partnership for Conservative Principles President Alfonso Aguilar, a one-time Trump supporter and conservative immigration activist who has been back and forth on his feelings on Trump's agenda, said he liked the rest of the President's statements in the speech on immigration but not VOICE.

"The majority of undocumented immigrants are good hard working people," Aguilar told CNN's John Berman on "Newsroom" Wednesday. "A small minority, and you're absolutely right, smaller than those in the general population, engage in criminal activity. So it is blown out of proportion. I don't know -- I think the office is just going to keep statistics and things like that, but I think if they do the research (they'd) realize that the majority of undocumented immigrants are really not involved in criminal activity."

Vermont Sen. Bernie Sanders criticized Trump's use of victims of tragedy to promote his agenda.

"The murder of anyone is a tragedy, and our hearts go out to all families who lose a loved one to violence," Sanders said in a Facebook post . "But let's be clear about what Donald Trump is doing tonight in inviting family members who saw a loved one murdered by an undocumented immigrant. He is stirring up fear and hatred against immigrants and trying to divide our nation."

Sanders also mentioned victims of hate crimes by non-immigrant perpetrators, wondering why Trump did not mention them.

"President Trump, any murder is a tragedy. Don't use these tragedies to stir up divisions by race and nationality," Sanders said.

"The obvious intent of a provision like that is to provide a misleading view of what sanctuary jurisdictions are really doing," Omar Jadwat, director of the American Civil Liberties Union's Immigrants' Rights Project, told CNN in January.