Senators at Immigration Hearing Clash Over Boston Bombings Senator Patrick J. Leahy, center, Democrat of Vermont, took issue with efforts to link the immigration debate to the Boston Marathon bombings. WASHINGTON - After months of heated negotiations, a bipartisan group of eight senators finally achieved compromise, coming together to unveil a broad overhaul of the nation's immigration laws. But at a Senate Judiciary Committee hearing on the legislation Monday, a new set of divisions began to emerge, offering an early glimpse at the partisan politics likely to be on display as the immigration bill winds its way through the Senate. At the marathon session, which featured testimony from 23 people, both lawmakers and witnesses raised charged questions. Could an immigration overhaul be done in separate pieces, without including a path to citizenship? What protections, if any, do same-sex couples deserve? How should the Boston bombings affect the immigration debate? The tempers of legislators flared, and at one point the hearing needed to be gaveled back to order. Senator Patrick J. Leahy, Democrat of Vermont and the chairman of the committee, took issue with conservative commentators and Republican lawmakers who suggested that any debate about an immigration overhaul should take into account that the two suspects in the Boston bombing emigrated to the United States from Kyrgyzstan. "Last week, opponents of comprehensive immigration reform began to exploit the Boston Marathon bombing," Mr. Leahy said. Let no one be so cruel as to try to use the heinous acts of these two young men last week to derail the dreams and futures of millions of hard-working people. At the committee's first hearing to review the new legislation on Friday, Senator Charles E. Grassley of Iowa, the ranking Republican on the committee, said that immigration changes should be done carefully, "particularly in light of all that's happening in Massachusetts right now and over the last week." On Monday, Senator Rand Paul, Republican of Kentucky, seemed to underscore the concerns of some Republicans when he sent a letter to Senator Harry Reid of Nevada, the majority leader, arguing that in light of the Boston bombings, "we should not proceed until we understand the specific failures of our immigration system." The mood quickly turned tense when Senator Charles E. Schumer, Democrat of New York and a member of the bipartisan group that drafted the new legislation, seemed to criticize his fellow senators, who, he said, "are pointing to what happened, the terrible tragedy in Boston, as, I would say, an excuse for not doing a bill or delaying it many months or years." "I never said that!" said Mr. Grassley, raising his voice and leaning forward in his chair to look at Mr. Schumer. I never said that! "I don't mean you, Mr. Grassley," Mr. Schumer said, as Senator Jeff Sessions, Republican of Alabama, accused Mr. Schumer of "demeaning the witnesses," and Mr. Leahy banged his gavel to restore order in the hearing room. The two brothers suspected of perpetrating the bombings came to the United States through the existing legal immigration system, under a 2002 asylum petition by their father, who said he was worried about his safety because of his activities in Chechnya. One of the brothers had become a naturalized citizen, and the other was here legally on a visa, though his citizenship was still under review after a routine background check revealed that he had been interviewed by the F.B.I. in 2011. Senator Ted Cruz, Republican of Texas, touched on another sensitive point when he suggested that instead of passing a broad bill, the Senate should take a piecemeal approach, focusing on areas "where there is wide bipartisan agreement." "I don't think that there is any issue in this entire debate that is more divisive than a path to citizenship for those who are here illegally," he said. In my view, any bill that insists upon that jeopardizes the likelihood of passing any immigration reform bill. Though the bipartisan group has insisted that any legislation must be comprehensive - Democrats, in particular, fear that they would not be able to secure support for a path to citizenship if lawmakers were allowed to vote on that issue separately - Mr. Cruz seemed to echo some House Republicans, who have suggested breaking the bill up into smaller parts and focusing on its less controversial components. Another touchy point - that the bill currently does not include same-sex couples for family unity consideration - came up during the testimony of Jim Kolbe, a former Republican congressman from Arizona who is gay and who endured a yearlong separation from his partner, a Panamanian immigrant, when the man's work visa expired. "Families like mine are left behind as part of this proposal," Mr. Kolbe said. Equally important, U.S. businesses and our economy suffer because of the omission of lesbian, gay, bisexual and transgender families from the bill introduced last week. Several Republican members of the bipartisan group have explicitly said that adding such protections would doom the legislation.