Outside contributors' opinions and analysis of the most important issues in politics, science, and culture.

Congress this week failed to come up with a solution to protect undocumented people who have been shielded from deportation under the Deferred Action for Childhood Arrivals program. The program is now set to end on March 5, six months after US Attorney Jeff Sessions announced that the Trump administration planned to phase out DACA, which has protected as many as 800,000 undocumented people.

The failure to protect these people would be a tragedy, because the program has changed many, many lives for the better, as my research and that of others has shown. It took them out of limbo and let them contribute to their families, communities, and the US economy.

When the Obama administration launched DACA in 2012, it amounted to a natural experiment: What would happen if you gave a portion of the overall population of undocumented immigrants fresh access to employment and other opportunities?

Immigrants who applied for protection under the program — enrollment is not automatic — were at least temporarily shielded from deportation. They also got temporary Social Security numbers and two-year work permits. To qualify, they had to have arrived in the US before 2007 (at 15 years old, or younger), been 30 or younger in 2012, and either have a high-school degree or be enrolled in high school or similar educational program.

When the program began, I started a national research project to study the effects on its beneficiaries. Those effects were profound: Under DACA, beneficiaries saw increased educational attainment, higher social mobility, and better mental health.

My research into undocumented immigrants predates DACA. From 2002 to 2015, I followed 150 undocumented young adults in Los Angeles, examining how they transitioned to adulthood in a context of limited rights. In Lives in Limbo: Undocumented and Coming of Age in America, I compared a group of people who attended college with a group that had left school at or before high school graduation.

Before DACA, undocumented immigrants could not translate academic achievement into professional success

Pre-DACA, even those young adults who had attained advanced degrees found their work and life outcomes limited — and unusually similar to those of less-educated peers. Lacking Social Security numbers, driver’s licenses, and other credentials, college graduates found they had little choice but to enter the informal, low-wage labor market.

In 2011, I sat across an auto assembly plant lunchroom table from Jonathan, who had not graduated from high school, and Ricardo, who had two postsecondary degrees. If Ricardo had been a citizen, he would have had his choice of attractive job possibilities, but both, now in their late twenties, faced the same limited work options.

Many people I interviewed described chronic headaches, toothaches, ulcers, difficulty sleeping problems, eating disorders, and thoughts of suicide. They had grown up in communities around Los Angeles and (as a result of the 1982 Supreme Court decision Plyler v. Doe, which opened the door to a K-12 education) they had attended school alongside American-born and citizen peers.

But at a critical stage in their lives, their immigration status blocked important rites of passage — they couldn’t get getting driver’s licenses, after-school jobs, or financial aid for college. (Many colleges would allow them to enroll, but they were disqualified from federal financial aid.)

Life in the shadows enacts a heavy toll. In my book, using a term from sociology, I argued that illegality was a “master status”: a binding constraint that overwhelmed all other traits and achievements. It acted as a lead weight that eventually dragged them down.

The undocumented young adults in my study were the embodiment of Langston Hughes’s “dream deferred.”

DACA opened doors, and eased stress

But with DACA, things changed for many of these same people. In 2013, my research team surveyed nearly 2,700 DACA-eligible young adults. Moreover, beginning in 2015, we carried out two waves of in-depth, in-person interviews with 481 DACA beneficiaries in six states: Arizona, California, Georgia, Illinois, New York, and South Carolina.

Just 16 months into the program, 59 percent of respondents reported having found a new job. Over one-fifth of the people we surveyed had obtained a paid internship.

Undocumented immigrants aren’t forbidden from having credit cards or bank accounts, but having a Social Security number makes getting these financial tools a lot easier. Almost one-half of our survey respondents opened up their first bank account after receiving DACA, and a third acquired their first credit card. Close to 60 percent of our respondents had obtained a driver’s license.

Twenty-one percent of those we surveyed reported that their access to health care had improved, sometimes because they had access to health plans provided by schools or employers.

DACA’s benefits appear to be greatest for people with degrees from four-year colleges. They were more than 1.5 times as likely to obtain new jobs and increase their earnings than DACA beneficiaries who never went to college. It seems they were finally able to make full use of their credentials and networks.

Our findings are now a couple of years old, but they have been corroborated. Six months ago, the political scientist Tom K. Wong, of UC San Diego, released results from a similar survey of DACA beneficiaries that found that 69 percent of respondents reported moving to a job with better pay. More than half moved to a job that they thought better fit their education and training, or offered better working conditions.

Much of the political and media coverage of this group has focused on the academically gifted, but, in terms of distance traveled, DACA’s biggest success stories involve moderate achievers. Most undocumented immigrant youth end their schooling before entering college. (In fact, more than 40 percent fail to complete high school.)

Many of our respondents reported that DACA led them enroll in community college or in jobs-training programs sponsored by community-based organizations. DACA beneficiaries who completed certificate or licensing programs — in fields like nursing, dentistry, construction, and cosmetology — experienced significant growth in salary. Sixty-eight percent who did so told us their hourly salaries increased from the $5-to-$8 range to more than $14 an hour.

Employers benefit, too, when they can hire qualified beneficiaries of DACA

Less tangible, but equally important, is DACA’s positive role in improving the mental health and general well-being of its beneficiaries. More than two-thirds of recipients told us they were less afraid of law enforcement and of being deported. (Fifty-nine percent of our respondents say they would report a crime now in a situation when they wouldn’t before.)

Being able to get a driver’s license or to obtain lawful employment is about more than transportation and work: It’s about not having to always look over your shoulder. Nearly 70 percent indicated that they feel less stress in general.

Eighteen-year-old Carolina, who is from Illinois, told us, “My freshman and sophomore year, I did really bad [in school], mostly because I was just not motivated because … all of this is going to be worthless in the end.” With DACA, her mindset changed: “OK, I actually have a chance,” she said.

Failing to replace DACA would also have negative consequences for the schools, hospitals, tech firms, courts, and community organizations for which this population is now able to work. There are now thousands of “DACAmented” teachers in US schools.

While not a perfect policy — only a pathway to citizenship would offer that — DACA has provided a significant boost to a large number of young people. The research is clear that DACA beneficiaries have made truly impressive economic and educational gains.

Our elected officials still have a chance to correct the mistake of ending this important program. Failing to do so would hurt the lives of thousands of people in cruel fashion and to no purpose. It would be a stain on the soul of our nation.

Roberto G. Gonzales is professor of education at Harvard University and author of Lives in Limbo: Undocumented and Coming of Age in America.

The Big Idea is Vox’s home for smart discussion of the most important issues and ideas in politics, science, and culture — typically by outside contributors. If you have an idea for a piece, pitch us at thebigidea@vox.com