The Senate’s pending immigration bill includes roughly 400 exemptions, exceptions, waivers, determinations and grants of discretion.

The bill’s complexity is forcing opponents and supporters to comb through its 844 pages before they can declare their conditional support or opposition to the high-stakes measure.

“WAIVER.—The Secretary, in the Secretary’s sole and unreviewable discretion, may waive the application of subparagraph (A) on behalf of an alien,” says one passage on page 71 of the complex document.

The prospective beneficiary of that discretion by a political appointee, according to the bill, is “an alien who departed from the United States while subject to an order of exclusion, deportation, or removal.”

The document mentions “discretion” or “discretionary” 41 times.

It mentions “judge” or “judges” 73 times, and mentions “secretary” 1018 times, normally as the people who decide whether to apply a waiver, exemption, determination or exception.

The complexity has already sparked GOP objections from Sen. Jeff Sessions and other Republicans who say they should be given more time to study and then explain the bill’s myriad complexities and loopholes to the public.

Top Democratic leaders, including Sen. Chuck Schumer, hope to push the bill quickly through the committee and then to the floor by early June.

The eight Senators who drafted the measure in secret for several months are expected presented their bill to the public on Thursday.

The bill mentions “exempt” or “exemption” 18 times.

“The competition requirement under section 253(a) of title 41, United States Code, may be waived or modified by a Federal agency for any procurement conducted to implement this title or the amendments made by this title if the senior procurement executive for the agency conducting the procurement … determines that the waiver or modification is necessary,” the bill declares on 142.

“Except” appears 156 times in the document.

On page 12, one exception allows the secretary to bypass the enforcement mechanisms that limit the award of green cards to former illegal immigrants.

“(B) EXCEPTION.—The Secretary shall permit registered provisional immigrants to apply for an adjustment to lawful permanent resident status if — (i)(I) litigation or a force majeure has prevented one or more of the conditions described in clauses (i) through (iv) of subparagraph (A) from being implemented.”

There’s also a “hardship exception” under Section 245D.

“The Secretary may adjust the status of a registered provisional immigrant to the status of a lawful permanent resident if the alien … demonstrates compelling circumstances for the inability to satisfy the requirement.”

Thee are 94 uses of “waiver,” including a provision on page 198 that allows the secretary to invite a deported illegal immigrant to return and file for the amnesty.

“WAIVER.—The Secretary may waive the application of subparagraph (A)(iii) on behalf of an alien if the alien ‘‘(i) is the spouse or child of a United States citizen … [or] … was physically present in the United States for an aggregate period of not less than 3 years during the 6-year period immediately preceding the date of the enactment of this section.

“Determines” is used 84 times in the bill.

“The Secretary of Homeland Security may permit an alien to remain temporarily in the United States and authorize the alien to engage in employment in the United States if the Secretary determines that the alien … has been helpful, is being helpful, or is likely to be helpful, in the investigation, prosecution of, or pursuit of civil remedies related to the claim arising from a covered violation.”

“Unreviewable” appears seven times in the bill.

On page 568, for example, the bill declares that “the Attorney General may, in the Attorney General’s sole and unreviewable discretion, appoint or provide counsel to aliens in immigration proceedings conducted under section 240 of this Act.”

The six other mentions of unreviewable authority apply to the secretary of the Department of Homeland Security.

In 2012, the immigration flow consisted of 450,000 working-age immigrants, 30,000 older immigrants and 700,000 short-term and long-term workers. The guest workers included roughly 50,000 agriculture workers, 400,000 service workers and 250,000 university-trained workers.

The new law would increase the inflow by at least 350,000 more workers, and exempt university-trained professionals from immigration caps, even when unemployment is above 8 percent.

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