The Republican establishment is considering a replay of 1986 only several times the size. What could possibly go wrong?

Fraud, perhaps? The 1986 IRCA implementation was noteworthy for fraud, called “out of sight” by an official involved in running it in the west.

Today’s officials are warning that the number of foreigners demanding to be processed would be “overwhelming” to the existing system and would allow criminals to slip through.

Immigration officials warn of amnesty ‘overload’, By Stephen Dinan, Washington Times, January 30, 2014

The officers who would be charged with approving millions of applications from illegal immigrants for legal status warned Congress this week that they can’t handle the workload, and said the change would guarantee criminals and others would be approved to remain in the country.

In a letter to House Republicans, who are planning to announce principles Thursday that would include legal status for the estimated 11 million illegal immigrants already in the U.S., the labor union that represents U.S. Citizenship and Immigration Services officers and adjudicators predicted it would be a disaster.

“There is no quality here, only quantity,” said Kenneth Palinkas, president of the National Citizenship and Immigration Services Council. “USCIS is not equipped to handle this workload, and due to political interference in its mission, is not empowered to deny admission to all those who should be denied due to ineligibility. We have become a visa clearinghouse for the world, rather than the first line of defense for a secure immigration system.”

Mr. Palinkas went on to say that any proposal that pushes millions of applications through would “overload the system.”

The letter was addressed specifically to House Judiciary Committee Chairman Robert W. Goodlatte, a Virginia Republican whose panel has jurisdiction over most of the key questions surrounding immigration policy.

While the law enforcement side of the immigration issue has gotten the most attention, analysts have warned that a major test for any legalization program would be whether the government bureaucracy could process the millions of applications.

Key questions include what documents would be accepted to prove someone meets the criteria for legal status and whether adjudicators would interview every applicant, which would take longer but would be more likely to weed out criminals or fraudulent applications.

Obama administration officials have said they would be ready if and when Congress orders them to begin processing.

They point to President Obama’s non-deportation policy for young adults, imposed last year, which granted tentative legal status to at least 400,000 illegal immigrants in its first year, as a test-run for a broader legalization.

The new union warning letter, however, indicates that the rank-and-file officers who make the judgments have less confidence that the system will be ready.

House Republicans are gathered at a retreat in Maryland on Thursday to talk about how to proceed on immigration. Party leaders want to pass bills that would grant some form of legal status to most illegal immigrants, and would grant a specific path to citizenship to young illegal immigrants.

The Senate passed a more generous bill last year that would grant a full specific pathway to citizenship to most illegal immigrants.

Mr. Palinkas asked for House Republicans to consult with his union before drawing up any final plans. He and the leaders of the unions representing the Border Patrol and U.S. Immigration and Customs Enforcement agents and officers have made similar requests to both the House and Senate.

Mr. Palinkas also took specific aim at House Majority Leader Eric Cantor, who has pushed for a path to citizenship for young illegal immigrants, known as “Dreamers.” Mr. Palinkas took issue with Mr. Cantor saying that granting them citizenship was in line with the founding principles of the U.S.

“If this were true, that would mean that all future Dreamers have a right to amnesty, as every immigration law is bypassed and permanently void. I hope, as the top member of the Judiciary panel, you would reject this language without hesitation,” Mr. Palinkas said in his letter to Mr. Goodlatte.