A Republican senator suggested Friday that the immigration status of two suspects allegedly involved in this week's deadly bombings in Boston might force lawmakers to rethink months of negotiations over how to overhaul the nation's immigration laws.

Sen. Chuck Grassley (R-Iowa). (AFP/Getty Images)

Speaking at the start of the first Senate Judiciary Committee hearing that began as a manhunt continued in Boston, Sen. Charles E. Grassley (R-Iowa) accused Democrats of "rushing" consideration of a bipartisan immigration bill unveiled this week and urged careful deliberations "given the events of this week."

"While we don’t yet know the immigration status of the people who have terrorized the communities in Massachusetts, when we find out, it will help shed light on the weaknesses of our system," Grassley said. "How can individuals evade authorities and plan such attacks on our soil?  How can we beef up security checks on people who wish to enter the U.S.?  How do we ensure that people who wish to do us harm are not eligible for benefits under the immigration laws, including this new bill before us?"

Moments later, Sen. Charles E. Schumer (D-N.Y.) urged colleagues to "allow the actual facts to come out before jumping to any conclusions about Boston."

"In general, we're a safer country when law enforcement knows who was here, has their fingerprints, photos, et cetera, has conducted background checks and no longer look -- needs to look at needles through haystacks," Schumer said. "In addition, both the refugee program and the asylum program have been significantly strengthened in the past five years such that we are much more careful about screening people and determining who should and should not be coming into the country."

Alex Conant, a spokesman for Sen. Marco Rubio (R-Fla.), another key author of the immigration bill, also urged caution: "There are legitimate policy questions to ask and answer about what role our immigration system played, if any, in what happened. Regardless of the circumstances in Boston, immigration reform that strengthens our borders and gives us a better accounting of who is in our country and why will improve our national security. Americans will reject any attempt to tie the losers responsible for the attacks in Boston with the millions of law-abiding immigrants currently living in the US and those hoping to immigrate here in the future."

The Judiciary Committee met Friday as part of an ongoing review of the immigration issue. Friday's hearing was the first on the immigration bill introduced this week with great anticipation after eight senators spent months sorting through the details.

But the hearing's lead witness, Homeland Security Secretary Janet Napolitano, was a no-show as she continues monitoring the situation in Boston.

Judiciary Committee Chairman Patrick J. Leahy (D-Vt.) announced Napolitano's change in plans at the start of the hearing as he also thanked law enforcement officials across the country for their work this week on the situation in Boston, the discovery of suspicious mail addressed to President Obama and Sen. Roger Wicker (R-Miss.) and the explosion at a chemical plant in West, Tex.

Grassley backed Napolitano's decision to cancel, saying that “We understand why the secretary can't be here, and we feel that she's doing exactly what she should be doing."

The committee is scheduled to meet again Monday to continue reviewing the legislation as part of a process that Democratic aides say will continue through May with committee meetings on immigration scheduled to occur at least twice a week. The full Senate would begin debating the immigration bill in June, assuming the committee eventually approves the legislation.

Grassley raised doubts about the forthcoming process from the start of Friday's hearing by telling his colleagues that "we're kind of off to a rough start" as he accused Democrats of "rushing to read and analyze" an 844-page bill.

He noted that exactly 30 years ago Friday -- April, 19, 1983 -- the same committee met to consider similar immigration legislation that would bolster border security and reunite separated families.

"Now 30 years have passed, and we're saying the same thing, facing the same problems," Grassley said. "We're proposing the same remedies and asking the American people to trust that we'll get serious about enforcing our immigration laws."

Sen. Jeff Sessions (R-Ala.) was also skeptical: "We have laws today that are utterly ignored, and I have no confidence that this administration, based on what we’ve seen, will ever enforce any law," he said.

But Schumer defended the team of eight senators who worked on the proposal.  "I believe one of the words that most signifies this bill is 'balanced,'" he said. "That's why we were able to get eight people of very diverse views to agree to a bill, and I think the American people will find it the same."

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