Why has the Donald Trump candidacy—which so many professionals and pundits at first dismissed as a joke—flared this summer? In the first week of July, 15 percent of Republicans supported Trump for president in a YouGov poll. By the third week, that support had almost doubled, to 28 percent—with another 10 percent listing him as their second choice.

Something happened in July to send Trump’s numbers soaring. That something may have been the murder of Kathryn Steinle.

On July 5, the 32-year-old Steinle posed with her father for a photograph on a San Francisco pier at 6:30 on a Wednesday evening. Suddenly there was a pop. Steinle crumpled. She died in hospital two hours later.

The stunningly random killing left behind a devastated family—and a confessed killer: Juan Francisco Lopez-Sanchez, an illegal immigrant from Mexico who had been convicted of seven previous felonies and five times been ordered deported from the United States.

In 2009, Lopez crossed the border into the United States again, was caught, and was sentenced to four years in federal prison. After his federal sentence was served, Lopez-Sanchez was handed over to San Francisco authorities to face trial for a local drug charge. The local court dismissed the charge and ordered the Lopez-Sanchez released into the community. Nobody notified federal immigration authorities, because San Francisco law forbids such cooperation.

It’s often remarked that Donald Trump appeals to angry voters. That’s surely true. Yet there is a delicate discomfort about mentioning exactly the issue those voters—at least, those Republican voters—say they are most angry about: the breakdown of immigration enforcement. Trump holds a 2-1 lead over Jeb Bush among Republicans who want an immigration policy that focuses on enforcement and deportation.

Many leading politicians have expressed concern over Kathryn Steinle’s sad death. They typically represent the crime as something aberrational. Hillary Clinton, for example, said that San Francisco authorities “made a mistake” when they released Lopez-Sanchez into the community. Jeb Bush said, “The system broke down for [Steinle] and her family, and you can see why people are upset about that.”

Trump, however, had already staked out a position that defined the Steinle killing as anything but aberrational. The system didn’t break down for Steinle. It functioned as it all too often does. As Senator Ted Cruz pointed out during a July 21 Judiciary Committee hearing on crimes by illegal immigrants, in 2014 alone, immigration authorities released into American communities 193 illegal immigrants with homicide convictions, 426 people with sexual-assault convictions and 16,000 with drunk-driving convictions. Altogether, 104,000 people who by law should have been deported were instead allowed to remain on American soil. The director of the agency in charge of the removals offered as a partial excuse that immigration courts faced a backlog of 500,000 cases.

Whatever the cause, there’s no doubt that removals of immigrants convicted of criminal acts have tumbled in Obama’s second term, after a sharp rise in his first term. Federal immigration authorities removed more than 216,000 such immigrants from the United States in fiscal year 2011, more than double the removals of fiscal 2007. But in fiscal 2014, only 178,000 were removed—a 17 percent drop from the 2011 peak.

Yet even as deportations drop, the flow of new illegal immigrants appears to be accelerating. Since illegal immigration is difficult to measure, many experts use the rate of apprehensions at the border as a rough proxy for the overall flow. After a recession-induced pause in 2008-2010, apprehensions of would-be border-crossers jumped 15 percent in fiscal 2013 over fiscal 2012—and then spiked 16 percent further in fiscal 2014 over fiscal 2013.

In his June 16 announcement speech, three weeks before Steinle’s death, Trump seized the issue of crime by immigrants, especially immigrants from Mexico:

When Mexico sends its people, they’re not sending their best. They’re not sending you. They’re not sending you. They’re sending people that have lots of problems, and they’re bringing those problems with us. They’re bringing drugs. They’re bringing crime.

They’re rapists. And some, I assume, are good people … But I speak to border guards and they tell us what we’re getting. And it only makes common sense. It only makes common sense. They’re sending us not the right people.

Republican politicians condemned and repudiated Trump. Business partners severed their relationship with him. Former Texas governor Rick Perry called Trump a “cancer” on the Republican party, and Rupert Murdoch tweeted: “Mexican immigrants, as with all immigrants, have much lower crime rates than native born. Eg El Paso safest city in U.S. Trump wrong.”

Trump’s many critics have rightly denounced the reckless accusations by an apparently self-serving figure. Yet in their determination to quell Trump’s overheated rhetoric, Trump’s critics risk straying into an opposite and also dangerous error: denial of important facts that matter to many voters, but that awkwardly challenge the elite consensus on immigration policy.

Rupert Murdoch was by no means the only person to claim in the wake of the Steinle killing that immigrants commit crimes at lower rates than the native born. Yet this claim, while literally true, is much less reassuring than the claimants imagine, for four crucial reasons:

First, by any definition, unauthorized immigrants commit a lot of crimes.

In 2011, the Government Accountability Office delivered a major report on criminal activity by unauthorized immigrants. The GAO was able to locate the arrest and sentencing records of roughly half the immigrants in local jails and state and federal prisons, and then sampled them to estimate what they contained. Here’s what it found:  

  • An estimated 25,000 of these undocumented immigrants serving sentences for homicide
  • A cumulative total of 2.89 million offenses committed by these undocumented immigrants between 2003 and 2009 (although half a million of these were for immigration-related offenses)
  • Among those offenses: An estimated 42,000 robberies, 70,000 sex crimes, 81,000 auto thefts, 95,000 weapons offenses, and 213,000 assaults

Second, crime by the unauthorized, like the population of illegal immigrants itself, appears to be disproportionately concentrated in border states. A Texas Department of Public Safety report obtained by the PJMedia estimated that the illegal immigrants in Texas prisons had committed a total of 2,993 homicides in a state that typically suffers between 1100 and 1400 homicides per year. After years of welcome decline, crime rates are rising in immigration hubs including Houston, Milwaukee, Phoenix, and San Diego.

Third, statistics on contemporary immigrant crime likely contain a downward bias. When most studies report that immigrants commit fewer crimes than natives, many rely—as I did above—on incarceration rates. Prison populations are the most authoritative source of data on immigrant crime. It’s much easier to assess the immigration status of a person in custody, after all.

But because U.S. prison sentences are so long, prisons house many people whose criminal activities occurred years, or even decades, in the past. Many of the people in prison today were sent there at a time when the foreign-born population was smaller and crime rates were higher. The Department of Homeland Security estimates that 20 percent of the U.S. prison population is foreign born. That does not imply that foreign-born persons are committing only 20 percent of crime right now. Yet that is how the statistic is often used.

Fourth, the native-born crime rate is an aggregate of every sub-population in the country, some of which have low crime rates, some much higher. Among those native-born groups with higher rates of crime: children of immigrants, who offend at rates substantially higher than their parents. Because the children of recent immigrants account for so much of U.S. population growth, higher immigration of groups with higher crime rates must drive crime levels higher than they otherwise would have been. That's just arithmetic.

American immigration policy has built a population that is younger, less educated, and poorer than it would otherwise have been. It has built this population at a time when young, less-educated people face narrower opportunities than young, less-educated people did two generations ago. The United States has become a society in which it’s harder for poor and less-educated newcomers to succeed, even as its immigration intake has tilted ever more sharply in favor of the poor and less-educated.

When American elites debate immigration, they mostly ignore this, and instead debate its economic impact. But even the most favorable analysis concedes that the economic benefits of immigration to the native-born are exceedingly small: about 0.2 percent of GDP, in a computation frequently cited and endorsed by the Obama administration.

In return for those relatively meager economic benefits, the United States shoulders many serious and severe social costs, including the crimes tallied by the GAO.

Under different immigration rules, and a different enforcement regimen, Kathryn Steinle would still be alive. Under different immigration rules, many thousands of other crimes would have been prevented. Under different immigration rules, the average U.S. crime rate might be lower than it is today—and probably considerably lower than it will be in future.

What to do in the face of those truths is challenging and unobvious. But one thing should not be done: to leave it only to Donald Trump to speak them aloud.

In a democracy, it’s the job of citizens to identify problems—and the job of elites to devise solutions. Elections should be competitions between elite groupings as to whose solutions will prevail. Immigration is an issue on which American elites refuse to do their jobs. Voters are intensely divided over immigration; political and business elites are almost unanimously united. On voting day, citizens are offered no choice—which means that the elite decision carries no legitimacy, since citizens were never given an effective opportunity to choose something different. By joining in a policy cartel, elites discredit themselves.

Donald Trump is a troubling figure. The voters (temporarily) surging to him are deluding themselves. But the politicians and media who want to blame Trump or his supporters can find the real culprit in their own mirrors.