(CNN) -- High levels of illegal immigration and crimes committed by unauthorized immigrants are among the key rationales cited by some supporters of a tough new immigration law in Arizona. "Border violence and crime due to illegal immigration are critically important issues to the people of our state," Arizona Gov. Jan Brewer said at the signing of the controversial bill, SB 1070. "There is no higher priority than protecting the citizens of Arizona. We cannot sacrifice our safety to the murderous greed of the drug cartels. We cannot stand idly by as drop houses, kidnappings and violence compromise our quality of life."
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FBI statistics: Violent crimes reported declined by nearly 1,500 over four years
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Reported property crimes also fell, by about 8,000, between 2005 and 2008
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CNN Fact Check: Kidnapping is up in Phoenix, but murderers' status can't be proven
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Arizona immigration trends murky, largely due to declining border apprehensions
A CNN Fact Check found that the senator's claim about the murders in @placeholder cannot be proven, but he did have police statistics to back up his claims of the city's high number of kidnappings, although its exact standing in the world is not clear.