The two long-shot candidates from two parties diverged on one issue—immigration—and found common ground on another: how to deal with mental illness in the U.S. prison population.
Illegal immigration was top-of-mind among the conference attendees. In a Q&A session after Carson's speech, Dave LaBahn, the president of the Association of Prosecuting Attorneys, asked Carson about the "burdens" that are placed on local police officers when legal and illegal immigrants aren't assimilated into American society.
"In terms of assimilation, English is the official language of this country," Carson said. "I don't mind what people do in the privacy of their own homes ... but the official language of our nation is what should be required in our school systems and in our work environments."
He added that someone who speaks English "should never feel uncomfortable in his own country," eliciting applause from the audience.
Carson said the U.S. should deal with illegal immigration by sealing the borders—"north, south, east, and west"—and by taking undocumented immigrants off welfare while implementing a guest worker program for them. Carson added that an insecure border also represents a terror threat.
"There are Islamic jihadists who wish to destroy us," Carson said. "They are growing, they are metastasizing throughout the world."
Webb's stance on immigration was decidedly less popular with the crowd. He touted an amendment he introduced in the Senate that would have provided a path to citizenship to immigrants who have been living in the U.S. illegally for five years and have "put roots down" in their communities.
The event's host said sheriffs have to bear a heavy cost of "illegal aliens" crossing the border and overcrowding jails, and asked Webb what he would do as president to enforce immigration laws.
Webb said that he would try to discourage border crossings, but said the government has to recognize that it is not feasible to deport the 11 million undocumented immigrants already living in the U.S.
"I would want to see our foreign policy focus more heavily on solving the problems in Mexico and Central America," Webb said. "The greatest challenge that we can solve is to work to stabilize the governments in Mexico and Central America so there is a different environment down there."
While criminal-justice reform is still gaining momentum among Republicans in Congress, the next frontier that politicians will have to consider is its intersection with mental illness and drug abuse. A 2014 study from the American Psychological Association found that 64 percent of jail inmates reported mental health concerns.
The conference's host asked Carson for his assessment of mental health care in the U.S.
"It's a significant problem. We don't adequately take care of the people who are mentally ill in our society," Carson said, adding that jail is "exactly the wrong place for them to be."