MOBILE, Ala. (WALA) – With hundreds of thousands of convicted or accused criminals, run-of-the-mill illegal immigrants who skip court simply are not a high priority, according to immigration experts.

That likely is one reason why Domingo Marcos Diego was free in Mobile County last week even though an immigration judge had ordered him to be deported. Last week, according to Mobile County prosecutors, the 16-year-old was behind the wheel of a car during a traffic accident in Semmes that claimed the life of Sonya Jones.

A judge on Monday ordered Marcos Diego jailed pending trial on a vehicular homicide charge. But authorities contend Marcos Diego never should have been in the country in the first place. The deportation order came about a year after he failed to appear for a court hearing in October 2017 to pursue an asylum claim after an arrest earlier that year that placed him in deportation proceedings.

After Marcos Diego disappeared, the Guatemalan native became a low priority for Immigration and Customs Enforcement officers. Jessica Vaughan, director of policy studies at the Center for Immigration Studies, said ICE officers are overwhelmed by the sheer volume of illegal immigrants on the run – many of whom have been convicted or accused of other crimes.

“The reality is, even if you skip out on the process, you’re probably not gonna come to the attention of ICE or be a target of ICE unless you’ve also committed another crime,” she said. “And so, it’s just a matter of ICE doing triage.”

ICE does not regularly publish data on at-large illegal immigrants, but information gathered this month under the Freedom of Information Act by the Immigration Reform Law Institute indicates that 644,488 illegal immigrants just from Mexico and Central America are free in the United States despite final deportation orders. Another nearly 1.1 million illegal immigrants from those countries remain free with pending immigration cases.

The Center for Immigration Studies, which favors stricter enforcement, found in 2015 that 179,040 at-large illegal immigrants with deportation orders had been convicted of other crimes.

Vaughan said it stands to reason that ICE will prioritize illegal immigrants with criminal records over non-criminals who skipped immigration court hearings.

“They’re going to spend time and resources on people they know are a threat,” she told Fox 10 News.

Vaughan said ICE has a harder time because of “sanctuary” jurisdictions that limit cooperation with federal immigration officers. Vaughan’s Washington-based think tank this month updated its tally of sanctuary jurisdictions, finding some 300 cities, counties and states across the country that refuse to honor hold requests from ICE under some circumstances.

Alabama does not have any sanctuary havens, but some nearby cities and counties do, including New Orleans, Jackson, Miss.; and Georgia’s DeKalb and Clayton counties.

The more time ICE agents must spend tracking down criminals who have been released by local jails, the less time they have to find hundreds of thousands of lower-priority illegal immigrants, Vaughan said. She added that ICE has a much easier time when local jails turn over illegal immigrants.

“They are able to manage criminal caseloads with far fewer officers,” she said.