WASHINGTON — Senators grilled Tucson Police Chief Chris Magnus about his views on immigration enforcement and enacting COVID-19 measures as they considered his nomination for Commissioner of U.S. Customs and Border Protection on Tuesday.

In a Senate Committee on Finance hearing, Magnus said his aim would be to treat migrants humanely while properly enforcing immigration laws. This comes after the Biden administration halted Border Patrol agents’ use of horses due to concern over treatment of Haitian migrants in Del Rio, Texas last month.

“I don’t believe we have to sacrifice efficiency for humanity,” Magnus said.

Sen. Elizabeth Warren, D-Mass., asked Magnus to commit to a transparent investigation into the “cruel and disturbing behavior” by Border Patrol agents in Del Rio. Magnus agreed and said he would issue a public release of the findings.

“Training has to go all the way back to the academy level, where people first start. In fact, I think you could make a credible case that it goes all the way back to the traits and characteristics that you look for in the people that you hire,” Magnus said, emphasizing that treating migrants humanely starts at the hiring process.

When answering questions at the hearing, Magnus underscored the significance of a strong relationship between local authorities and federal law enforcement, saying it could help alleviate the influx of illegal immigration into the United States.

Migrant encounters at the Mexico border reached a 21-year high in July 2021 at nearly 200,000 encounters — the highest monthly total since March 2000.

Sens. Tim Scott, R-S.C., and Todd Young, R-Ind., were persistent in asking Magnus whether or not he considered the situation at the border a “crisis,” to which he evaded the question.

“If we spent a little less time debating on what the terminology is, and perhaps a little more time trying to fix a broken system and working together, we could address what I’ve already acknowledged is one of the most serious problems that we face right now in our nation,” Magnus said.

Magnus said he would support testing migrants for COVID-19 and instituting a vaccine requirement for migrants entering the country, something that is not being done currently.

Warren re-introduced legislation in March that would require immigration detention facilities to collect and publicly report data about COVID-19 cases, vaccine distribution and preventative measures.

Magnus was nominated by President Joe Biden in April, but his hearing was delayed by several months.