President Trump has made no secret about his intentions to deport illegal immigrants. His statements as well as administrative actions to remove certain guidelines that focused enforcement efforts on criminals has understandably caused a lot of concern among illegal immigrants, their American families, and those concerned with their plight. They should take comfort that the Trump administration’s efforts to boost arrests, the necessary precursor to a deportation, are stymied by limited local and state law enforcement cooperation with the federal government when it comes to identifying illegal immigrants.

Recently released data on the number of arrests by Immigration and Customs Enforcement (ICE) shows that they are arresting many fewer illegal immigrants under Trump’s administration than under President Obama’s, at least through June of 2018. During the first full 17 months of the Obama administration, from February 2009 through June 2010, ICE arrested 437,671 illegal immigrants. For the same first full 17 months of the Trump administration, ICE arrested 226,138 illegal immigrants, about half the number arrested during the same period in Obama’s administration.

Relative to the last full month of the previous administrations, the number of ICE arrests under Trump is up by a whopping 37 percent (Figure 1). Over the same time, President Obama’s ICE was arresting 25 percent more people than under the last full month of the Bush administration, quite a significant increase on its own. The increase under Trump is larger as a percentage because it started from a low base, but the increase in the number of arrests under Obama was larger. For instance, the number of arrests under Obama was 5,803 greater in June 2010 than in December of 2008. At the same point in the Trump administration in June of 2018, the number of arrests was up 8,965 over December 2016.

There are two broad categories of arrests by the ICE. The first is called custodial arrests, which is when ICE picks up an illegal immigrant arrested by another law enforcement agency such as state or local police departments. The second is called ICE arrests, which is when ICE itself arrests illegal immigrants on the streets. Figure 2 shows that the number of custodial arrests have fallen dramatically since October 2008 while the number of ICE arrests has stayed relatively constant. This means that local and state non‐​cooperation with ICE works to reduce the number of ICE arrests as between 70 percent and 90 percent of those arrests are custodial over the entire time.

Some states, like Texas, are fully cooperating with ICE when it comes to immigration enforcement while others like California are resisting mightily. In Texas, there were 3,963 ICE arrests in May 2018 compared to 2,584 in December 2016, a 53 percent increase. In California, there were 1,587 ICE arrests in May 2018 compared to 1,356 in December 2016, a 17 percent increase. ICE is more active everywhere in the country, in sanctuary states and non‐​sanctuary states, but the difference is stark across such jurisdictions.

The federal government under Presidents Bush and Obama convinced virtually every locality in the United States to sign up for the Secure Communities program that essentially turned over the vast majority of the arrested illegal immigrants to ICE for deportation. Since President Obama was a Democrat, there was little initial political opposition to the massive increase in states and localities cooperating with the feds via Secure Communities – especially in Democratically controlled states with large numbers of illegal immigrants. However, political reluctance to cooperate via Secure Communities built rapidly. In 2011 Massachusetts, Illinois and New York requested to opt out of the program. States like California then limited statewide cooperation with ICE and then President Obama replaced Secure Communities with a less punitive version called the Priority Enforcement Program that targeted criminals, which was in effect from 2015 to 2017. Today, most states and localities with large numbers of illegal immigrants are not cooperating with President Trump’s ICE nearly as much as they cooperated with President Obama’s ICE – which is preventing Trump from arresting and, eventually, deporting large numbers of illegal immigrants.

There are other, lesser reasons why the Trump administration is unlikely to reach President Obama’s deportation record. One is bureaucratic incompetence in the Department of Homeland Security, the Department of Justice, and other executive branch chaos that has so far prevented an orderly and organized deployment of law enforcement resources. As a partial result of those administrative problems, they are incapable of convincing states and localities to enforce federal immigration laws. Another reason is that illegal immigrants in 2018 are savvier than they were in the past, are better able to avoid law enforcement, and the few who were criminals were deported over the years, fewer new illegal immigrants have taken their place, and those remaining are less likely to come into contact with law enforcement.

State and local government reluctance to enforce federal immigration laws and cooperate with the Trump administration has limited its ability to arrest and, eventually, deport large numbers of illegal immigrants. At the current rate, ICE under the Trump administration will be able to arrest about half a million fewer illegal immigrants relative to the Obama administration even if President Trump serves two full terms. Those who are dispirited by the Trump administration’s efforts to deport large numbers of otherwise law‐​abiding illegal immigrants should take some solace that their efforts to block full local and state cooperation with ICE is bearing fruit.