DETROIT — Several U.S. governors have threatened to stop accepting Syrian refugees following last week's attacks in Paris, even as experts counter they lack legal authority to block the relocations.Florida Gov. Rick Scott wrote a letter Monday to House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell saying the state would "not support the requests we have received" for 425 Syrian refugees to resettle in Florida. However, Scott said, the state can't prevent refugees from coming to Florida with federal support and he demanded that Congress act to block Syrian refugees coming to the United States."Why wouldn't you take your time doing this, especially when you know that one of them posed as a refugee?" Scott said Monday night, referring to reports that one of the Paris attackers used a fake Syrian passport. "And we're going to say, 'Oh, we're okay?' No. You slow down and make a good decision before you go forward."Scott's letter came after several other Republican governors issued executive orders or made statements that they would oppose Syrian refugees relocating in their states in response to the attacks on the French capital last week that left 129 dead. Among them were Govs. Robert Bentley of Alabama, Greg Abbott of Texas, Asa Hutchinson of Arkansas and Bobby Jindal of Louisiana.President Barack Obama, whose administration recently pledged to accept about 10,000 Syrian refugees, argued that the United States needs to allow them because many are fleeing terrorism. "Slamming the door in their faces would be a betrayal of our values," he said at the G20 Summit in Turkey.Obama called on world leaders to continue accepting refugees from Syria, but only after "rigorous screening and security checks."Some state leaders disagree with Obama's assertion that the country can simultaneously welcome refugees seeking safety and ensure citizens' security. Several have called for a complete halt to resettlement, others for temporary delays, and a few seek more information from federal officials on the vetting process. The Homeland Security Department says refugees face the highest level of security screening of anybody entering the United States — a process that takes two years on average — but officials will work to allay states' concerns.While the resettlement of refugees is governed by federal law, states administer many of the programs intended to help people land on their feet once they arrive in the United States: employment assistance, health care, vocational training and English language courses, for example.Scott acknowledged that states can't stop the federal government from settling refugees in their communities, but some governors took a less-nuanced approach. Jindal, for example, issued an executive order invoking emergency powers granted to the Louisiana governor during "times of emergency or the threat of emergency."Abbott ordered Texas' refugee-resettlement program not to accept any more Syrians and, in a letter to Obama, the Republican also urged scrapping federal plans to accept more Syrian refugees into the country as a whole. He said the federal government can't perform "proper security checks" on Syrians. Arizona Gov. Doug Ducey called for an immediate halt and wrote he was "invoking our state's right … to receive immediate consultation by federal authorities" to address the state's concerns. Iowa GOP Gov. Terry Branstad acknowledged governors might lack authority, but added he wants more information about refugee placement and the vetting process.But Shalini Ray, a University of Florida law professor who specializes in refugee and immigration law, says governors are generally powerless when it comes to accepting refugees."(Scott's) letter reflects the fact that states lack authority to bar refugees from resettling within a particular state," Ray said. "Moreover, states cannot constitutionally discriminate among refugees based on race or ethnicity, as many other governors are attempting to do today."From Oct. 1, 2014, to Sept. 30 this year, 2,709 refugees from around the world made Florida home. Among them were 104 Syrians, most of whom settled in Hillsborough (36) and Miami-Dade (20) counties.The American Civil Liberties Union of Florida criticized Scott's action."By calling for the refugees fleeing Syria to be denied placements because of some perceived link between those fleeing violence and the perpetrators of that violence, Gov. Scott is letting fear take control," executive director Howard Simon said in a statement.Lavinia Limon, president and CEO of the U.S. Committee for Refugees and Immigration, said that under the Refugee Act of 1980, governors can't legally block refugees. Each state has a refugee coordinator, a post created as part of that law, she said. Funded by the federal government, the post coordinates resettlement efforts with agencies such as hers and directs federal funds for refugees.Westy Egmont, director of Boston College's Immigrant Integration Lab, said the law previously withstood state challenges partly because the federal government has worked to equally distribute refugees being resettled. Some states have worked with resettlement agencies to limit new refugee arrivals to those with family ties to the community while families or individuals with no ties to a specific state have been sent to other locations with better prospects for jobs, housing and integration programs. Refugees are generally invited to move to the United States after being referred to a State Department Resettlement Support Center by the United Nations High Commission on Refugees. In some cases, they can be referred by a U.S. embassy or nongovernmental agency. In other cases, potential refugees who are close relatives of people granted asylum in the United States or other refugees already in the country can apply directly with the U.S. government to move here. However, they must "belong to specific groups set forth in statute or identified by the Department of State as being eligible for direct access to the program," according to the State Department's U.S. Refugees Admission Program. Times/Herald staff writer Michael Auslen contributed to this report.