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The basics of the US immigration system

What is immigration reform?

In Washington, immigration reform typically refers to a set of proposals for a broad overhaul of the US immigration system. These proposals would increase border and interior enforcement, revamp the process for legal immigration, and address the 11.5 million unauthorized immigrants currently in the United States — generally by allowing them to apply for legal status and, in some cases, eventual citizenship.

The centerpiece of the immigration reform debate is the bill passed by the Senate in June 2013. (Its counterpart in the House is currently stalled, though House Democrats are trying to force a vote on it.) That bill addresses immigration comprehensively, but any of the components addressed in the bill — including the DREAM Act, high-skilled visa reform, or mandatory E-Verify — could be passed as immigration reform in their own right.

Some people favor an approach that would only ramp up immigration enforcement against unauthorized immigrants. And some immigrant-rights advocates prefer to focus on getting the Obama Administration to halt the increased levels of deportations in recent years.

Who are the immigrants currently in the United States?

As of 2011, roughly 40 million immigrants lived in the United States, according to the American Community Survey. The survey defines immigrant as any US resident who was born in another country.

Of that group, 36 percent were naturalized citizens, 32 percent were legal permanent residents, 4.2 percent were on nonimmigrant visas (including work and student visas), and 27 percent were unauthorized immigrants. That's according to research from the Migration Policy Institute and the Pew Hispanic Trends Project.


A little more than one-quarter of all current US immigrants come from Mexico. Another one-quarter come from South and East Asia. The Caribbean, Central America, and South America each contribute between 5 to 10 percent of the US immigrant population.

How many immigrants enter the country each year?

In 2012, the US government granted 584,784 immigrant visas. That includes green cards for permanent residents and visas for refugees and asylum grantees.


The United States also saw 3 million entries by people on work visas and 1.5 million entries by students on student visas. (This isn't the number of people, however, since some people made multiple entries.) The US government considers work and student visas temporary — in some cases, visas can be revoked if the government thinks the visa holder intends to stay long-term — so it counts them differently.

The US government also handed out roughly 42 million tourist and diplomatic visas in 2012.

The two main types of legal immigration are work-based and family-based immigration. Both of these rely on sponsors who already live in the United States.

On the work-based side, employers apply to sponsor would-be employees for temporary visas. These visas are capped. There are 65,000 H1B visas each year, the most common visa for high-skilled workers (although other visas for highly-educated workers are available). At the moment, companies hit this cap very quickly. There are 66,000 H2B visas for "low-skilled" workers a year; at the moment, companies also hit this cap, but not nearly as quickly as visas for high-skilled workers. There are no quotas for agricultural visas.

On the family-based side, US citizens and permanent residents with green cards can apply to sponsor their relatives for green cards. The wait time can vary based on the sponsor's citizenship status, the relationship, and the countries involved.

If a would-be immigrant does not have a relative or employer in the US willing to sponsor her, there are a few other options. If you're incredibly rich, you can come to the US on an investor visa. The diversity visa lottery offers 40,000 green cards a year to people in countries that haven't historically had large immigrant populations in the United States. Alternatively, would-be immigrants who fear persecution in their home country can apply for refugee status or asylum.

Other than that, it's impossible to come legally to live in the United States (setting aside tourist and student visas). Here's a helpful flowchart of this system.

What is the difference between a high-skilled and low-skilled immigrant?

High-skilled immigrants are typically professionals who have a degree in their field — often in science, technology, engineering, or medicine. They tend to come from Europe, South Asia, and East Asia. This category includes immigrants who arrived on H1-B visas and foreign students who stayed after graduation.

Low-skilled immigrants are those who work in blue-collar jobs, including construction, hospitality, maintenance, and agriculture. They commonly come from Latin America and arrive on either H2-B unskilled visas or H2-A agricultural visas.

There's broad agreement that having educated, skilled immigrants helps the US economy. Low-skilled immigration is more controversial politically, because of the fear that low-skilled immigrants will take American jobs and hurt US wages. (Many economists have found, however, that low-skilled immigrants don't necessarily drive down the wages of native workers — instead, they compete with other immigrants.) Immigrants of all skill levels can also boost the economy by spending their earnings back into their communities, and by starting businesses of their own that employ Americans.

What is an unauthorized immigrant?

An unauthorized immigrant is anyone who is in the United States but doesn't have any form of legal immigration status and, therefore, no legal authorization to be here. In 2013, there were approximately 11.3 million undocumented immigrants in the United States.

Approximately half of them entered the country illegally (in most cases, by crossing the border from Mexico into the southwestern United States). The other half entered legally — on temporary visas — but didn't leave the country when the visas expired: they're known as visa overstays.

Roughly 85 percent of undocumented immigrants have been in the US for at least five years, and the majority have lived here for at least 10 years. In 2013, the median unauthorized immigrant had lived 12.7 years in the US.

The unauthorized immigration wave peaked from 1996 to 2006:


Experts cite a number of reasons for the growth in the unauthorized population since 1996. Many believe the legal immigration system just couldn't satisfy US companies' demand for labor. Some cite poor immigration enforcement, especially at the workplace — on the other hand, others say that increased border security has made people less likely to leave. And some point to a 1996 law that made it more difficult for unauthorized immigrants to receive legal status while living in the United States.

About a third of the unauthorized immigrants in the United States have children who are native-born US citizens. An estimated 4.5 million US-born children have at least one unauthorized parent.

How does the United States patrol its borders?

Since 1996, the US has consistently ramped up immigration enforcement on both the border and interior of the country. There are currently 18,600 US Border Patrol agents deployed on the US-Mexico border. The border is also protected by 650 miles of fencing; a system of surveillance cameras sometimes called the high-tech fence; and 10 unmanned surveillance drones.

When an immigrant is caught crossing the border, the Border Patrol can do a few things:

1) Take the immigrant directly to the foreign side of the border, then release him immediately (known as catch and release). This is becoming increasingly uncommon. Under Bush, 25 percent of all immigrants who were caught in the US (by Border Patrol or Immigration and Customs Enforcement, which handles enforcement in the interior of the country), and did not have a criminal record, were returned to their home countries without charges. Under Obama, that number dropped to 10 percent.

2) Transport the immigrant to another part of the border or to the interior of Mexico in order to deter the immigrant from trying again.

3) Prosecute the immigrant in a criminal court on misdemeanor illegal entry charges or felony illegal reentry charges. This is becoming increasingly common—nearly one-third of federal criminal convictions in the United States in 2012 were for immigration-related offenses. This guarantees that the immigrant will be unable to reenter the United States legally for at least five years.

It's difficult to measure whether border enforcement affects the number of undocumented immigrants in the United States — it may deter future entries, but may also deter undocumented immigrants who are currently in the country from leaving. The increase in border security does, however, seem to be associated with an increase in people who die trying to cross the border.

How does deportation work?

Unauthorized immigrants are typically deported — removed from the country — after they are apprehended or taken into custody by federal immigration agents.

In theory, unauthorized immigrants are supposed to go through deportation proceedings in an immigration court, where a judge determines whether they really are unauthorized and ineligible for any sort of reprieve. This process can take several years, and the immigrant has no right to a lawyer. If the judge issues a removal order, then the immigrant is sent back to his or her home country.

In recent years, however, the court process has become less common. One-third of all deportations are now conducted through a process called expedited removal — anyone found within 100 miles of the US-Mexico border can be sent back immediately unless Border Patrol chooses to prosecute them in federal court instead.

In certain cases, legal immigrants who aren't citizens — including green-card holders — can be deported if they commit crimes involving moral turpitude. This is a fairly broad category and can include everything from murder to animal fighting.

How has the Obama Administration changed deportation policy?

The number of annual deportations rose dramatically under the George W. Bush administration, from under 200,000 in 2001 to 370,000 in 2008. The Obama administration has continued that pace, deporting roughly 400,000 immigrants each year.

A major reason for the rise in deportations has been greater cooperation between federal and local law enforcement. Under the federal Secure Communities program, every immigrant who gets checked into a local jail is run through a federal database to check his immigration status. Since 2009, this program has resulted in the deportation of more than 300,000 immigrants. This includes everyone from felons to unauthorized immigrants pulled over for traffic violations.

But the Obama administration has also said it wants to prevent certain unauthorized immigrants from being deported. The Administration issued several memos in 2010 and 2011 telling federal agents not to deport low-priority immigrants, especially immigrants who arrived as children or parents of US citizens. Field agents have, however, been extremely resistant to putting these memos into practice. In 2012, President Obama announced the Deferred Action for Childhood Arrivals program, which allowed certain immigrants brought as children to apply for protection from deportation and a work permit.

What is the DREAM Act?

The DREAM (Development, Relief, and Education for Alien Minors) Act was a proposed federal law that would cover young adults aged 15 to 29 who came into the country as children and have gone to college or served in the military. It would give these DREAMers legal status and allow them to apply for citizenship eventually.

The DREAM Act was first proposed in 2003 and last came up for a vote in 2010 — it passed the House but was blocked in the Senate by a Republican filibuster. Comprehensive immigration reform bills (such as the 2006 and 2007 bills proposed under President Bush, as well as the Senate immigration bill passed last year) contain a section that allows DREAMers to obtain legal status and eventual citizenship more quickly than other unauthorized immigrants.

As of May 2014, 21 states have their own DREAM Act laws that would grant in-state tuition at public colleges to undocumented immigrants who have grown up in the state. These are different from the federal DREAM Act, since states can't grant legal status or citizenship to undocumented immigrants.

In 2012, President Obama launched the Deferred Action for Childhood Arrivals program, which allowed DREAMers to apply for work permits and protection from deportation. This is often mistakenly referred to as Obama implementing the DREAM Act, but it isn't as permanent as the DREAM Act would have been, since immigrants have to re-apply every two years.

Can immigrants receive public benefits?

Some can, some can't. Here's a breakdown:

  • All naturalized US citizens can receive public benefits, such as tax credits or Medicaid, if they qualify. So can refugees, people who receive asylum, and victims of trafficking.
  • Green-card holders can receive federal benefits, but only after they've had their green cards for five years. States have the option to provide certain benefits, like Medicaid, to children and pregnant women with green cards even before then.
  • Immigrants on work visas, student visas, or tourist visas can't receive public benefits.

One big exception here are subsidies under the Affordable Care Act, or Obamacare, which are available to anyone who is lawfully present — that is, people who have entered legally and haven't violated the terms of their visa. (Immigrants who have received deferred action from deportation under the Deferred Action for Childhood Arrivals program are also eligible.)

Unauthorized immigrants are not eligible for public benefits. However, there are 4.5 million children who are US citizens but have at least one undocumented parent. These children are eligible for certain benefits, like the Child Tax Credit or food stamps.

See this table for more details.

What was the immigration reform bill the Senate passed in 2013?

In 2013, a bipartisan Gang of 8 senators introduced the Border Security, Economic Opportunity, and Immigration Modernization Act. This was a comprehensive immigration reform bill.

It passed the Senate 68-32 in June 2013, but was never introduced in the House. (A bill based on the Senate bill was introduced by House Democrats in October 2013 but has not been acted upon, despite Democratic attempts to force a vote.)

The Senate's immigration bill would do the following:

  • Provide a path to citizenship that would take 13 years for most of the unauthorized immigrants currently in the country, and less time for agricultural workers and DREAMers.
  • Increase border enforcement by allocating an additional $46.3 billion in funding for border security, and requiring the government to double the number of Border Patrol agents and fencing along the border.
  • Strengthen interior enforcement by making the E-Verify employment verification system mandatory for all employers, and instituting an entry-exit visa-tracking system to prevent people from overstaying their visas.
  • Expand and streamline legal immigration by clearing up the backlog of immigrants with pending applications; create a new green-card system that merges family-based and work-based immigration into a single pool and assigns immigrants "points" to determine their eligibility; and create a new renewable work visa for low-skilled workers, with annual quotas that depend on market demand.

Many of these components depend on each other — the bill is set up so that the path to citizenship doesn't kick in until certain security metrics have been met and the backlogs have been cleared. These conditions are known as triggers.

What is E-Verify?

E-Verify is an electronic system that allows employers to check the immigration status of any employee against federal records before hiring. Currently, it's used by fewer than 9 percent of employers.

E-Verify tends to figure heavily into immigration proposals. The Senate immigration reform bill would require all employers to use E-Verify within five years. In fact, this is the main way (along with an electronic entry-exit visa system) that the bill proposes to prevent future unauthorized immigration.

Other politicians, meanwhile, have suggested that E-Verify should be made mandatory now, without also legalizing unauthorized immigrants, on the grounds that the immigrants would become unable to find work and eventually leave en masse (this is often referred to as self-deportation).

It's worth noting that E-Verify isn't perfect. One 2009 study found that the system has a 2.9 percent error rate, which disproportionately affects naturalized US citizens and other immigrants, as well as women who have changed their names. What's more, when states (like Arizona) have made E-Verify mandatory, many employers still don't use the program.

What is an entry-exit visa system?

Roughly half of all unauthorized immigrants in the United States originally entered the country legally on temporary visas but then stayed once those visas expired. These are known as visa overstays.

Right now, there's no system to track visa overstays — immigration officials have no way of knowing whether someone left the country before his or her visa expired unless they somehow turn up elsewhere in the system (say, by getting arrested).

The 9/11 Commission recommended that the Department of Homeland Security develop an electronic entry-exit system to track visa entries and exits automatically — and alert officials when someone is overstaying their visa. So far, however, the agency hasn't figured out a cost-effective way to build this system.

The Senate immigration reform bill requires an electronic entry-exit system to be built within 10 years. It's one of the triggers that the government must meet before any formerly unauthorized immigrants who receive legal status can apply for green cards.

What are individual states doing on immigration?

In recent years, many individual states have carried out their own policies to make the lives of unauthorized immigrants either easier or harder. Here are a few examples.

Enforcement: In 2010, Arizona passed SB 1070, which would require police to ask anyone they stopped or detained for their immigration status. The bill also made it a state crime to be in Arizona without papers or to work while unauthorized. The Supreme Court permanently blocked most of the law — save for the provision requiring local police to check immigration status.

While some states sought to emulate Arizona's law, most were also defeated in court. Other states are working to limit the number of situations in which local police can hand unauthorized immigrants over to the federal government to deport.

College eligibility: Twenty-one states have passed their own DREAM Acts (not to be confused with the federal DREAM Act) that would grant in-state tuition at public universities to undocumented students who have grown up in the state. On the other side, Georgia, Alabama, and South Carolina have prohibited unauthorized immigrants from attending public universities at all.

Drivers' licenses: Some states have taken steps to restrict or expand drivers' licenses based on immigration status. Ten states (and the District of Columbia) allow unauthorized immigrants to receive licenses. In Arizona and Nebraska, conversely, state governments are attempting to redefine eligibility for drivers' licenses in order to exclude immigrants who've been given deferred action under the Obama Administration (who should be eligible given the text of their state laws).

What did the 1986 immigration reform bill do?

The Immigration Reform and Control Act of 1986, also known as the 1986 amnesty, allowed millions of unauthorized immigrants to apply for legal status. It also made it illegal for an employer to knowingly hire an unauthorized immigrant.

Before the law passed, there were 3.2 million unauthorized immigrants in the country; 2.7 million of them obtained legal status under the law. Yet many unauthorized immigrants failed to meet the bill's requirements. So, in 1988, the unauthorized population of the country was still 1.9 million. And it kept rising for the next 20 years, to 12 million in 2006, before decreasing slightly during the recession to 11.5 million today.

Critics of immigration reform today argue that the 1986 law took a flawed amnesty first approach that didn't pay enough attention to workplace enforcement. The bill essentially let employers off the hook if they accepted fake documents from employees — and so, spurred a growth in the market for fake documentation. What's more, employers who paid unauthorized immigrants off the books only got caught if the government happened to raid their workplace or audit them.

Immigration reform supporters, meanwhile, say that the big problem wasn't the 1986 law that granted amnesty. Instead, the problem was a subsequent 1996 law that escalated border security and made it harder for unauthorized immigrants to get legal while in the US. That law, they say, had the paradoxical effect of encouraging immigrants to stay in the United States and settle here with their families, rather than risking a dangerous border crossing, while forcing them to stay unauthorized.

What else should I be reading on the subject?

"Frequently Requested Statistics on Immigrants and Immigration in the United States," Migration Policy Institute

"The Economic and Political Impact of Immigrants, Latinos and Asians, State by State," Immigration Policy Center

"Unauthorized Immigrants: Length of Residency, Patterns of Parenthood," Pew Hispanic Trends Project

"Immigration Enforcement In The United States: The Rise of a Formidable Machinery," Migration Policy Institute

Summary of the Senate immigration bill from Sen. Robert Menendez (D-NJ), one of the authors

"Understanding Immigration Federalism In The United States," Center for American Progress


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