In debates over the immigration reform bill currently making its way through the Senate, a 1986 piece of immigration legislation passed under then-President Ronald Reagan has turned into a frequent touchstone for those who warn against enacting a bill into law which doesn't prevent against illegal entries into the United States.  Conservative opponents of the bill have hammered home the idea that the 1986 legislation, the Immigration Reform and Control Act (IRCA), granted legal status to about 2.7 million undocumented immigrants while failing to stanch the flow of illegal immigration into the country. 

Earlier this month, four of the most outspoken opponents - Senators Chuck Grassley of Iowa, Jeff Sessions of Alabama, Mike Lee of Utah, and Ted Cruz of Texas, all Republicans - published a joint open letter to their Senate colleagues warning that the Border Security, Economic Opportunity and Immigration Modernization Act of 2013 would repeat mistakes made in the 1986 legislation.  "Americans expect their government to end the lawlessness, not surrender to it," the letter read.

So what are some of the ways the 2013 plan is different from the 1986 bill?

1. The 2013 bill contains "triggers" which make the proffered path to citizenship contingent upon the elaboration and implementation of border security measures by the Department of Homeland Security (DHS).

This has been perhaps the most hotly contested point of late.  Many conservatives - even Marco Rubio, who co-authored the bill - argue against giving the DHS discretion over how the bill's border security goals are reached.  They want more specific means of achieving them to be made explicit in the legislation, indicating that they don't trust the government - especially not a department which would be reporting to Democrats, at least initially - to do what they feel is necessary to secure the border. 

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In the 2013 version, for current undocumented immigrants to receive provisional legal status, the DHS has to submit a strategy for US-Mexico border security and border fencing.  For them to be eligible to get lawful permanent resident status in 10 years, both security strategies have to be operational and an electronic exit system at air and sea ports of entry as well as an electronic employment verification system have to be up and running.  The latter, E-Verify, enables workers to "lock" their social security numbers and access their own past employment records to prevent and report fraudulent use.

By contrast, the much-maligned 1986 reform established no triggers pegging enforcement of immigration laws to legalizing measures.  What it did do was establish an employment verification system that introduced the I-9 form, on which employers attest that employees have provided proof of eligibility to work legally in the US, though without requiring employers to verify that. 

2. The Senate's plan has exceptions for DREAMers, or undocumented immigrants who were brought here as young children by their parents.

They can become legal permanent residents (green card holders) after five years, and apply for citizenship immediately afterward.  Nothing about this provision has precedent in the 1986 reform.

3. The 1986 bill did little to establish channels for future, legal immigration flows.

Beyond granting legal status to 2.7 million undocumented at the time, the crux of the IRCA was toward greater prohibitions rather than providing realistic channels for qualified immigrants to come legally.  It made it illegal to knowingly hire undocumented immigrants, increased funding for the Border Patrol, and introduced the aforementioned employee verification system.  It limited the total number of green cards for all lower-skilled workers across the United States to just 5,000, which the American Immigration Council calls "grossly insufficient". 

The visa system provided for in the 2013 bill would be enormously liberalizing - for immigrants in certain high-demand occupations, for example, between 60,000 and 125,000 visas would be available.  A new bureau created by it would track supply and demand in given industries and submit reports with suggestions on how the number of visas to be granted should be modified from year to year, giving the system a flexibility which current US immigration laws lack.