US Supreme Court dilutes Arizona immigration laws The US Supreme Court has diluted tough immigration laws introduced by the state of Arizona. Despite removing three key parts of the law the "show me your papers," the most controversial clause, remains. Opponents say by keeping the clause US citizens can be targeted by police based simply on their race or the colour of their skin. The ruling hands a crumb of comfort to both sides of the argument. Raul Grijalva is a Democrat who represents Arizona's 7th district on the Mexican border: "It is a split decision and I am very disappointed in the section that was found constitutional. I think it opens the door for increased violation of civil rights and discrimination. Mike Lee is a Republican Senator for Utah: We do have illegal immigration problems the states are saddled with a lot of challenges as a result of federal government's failure to enforce the border and to enforce our set of immigration laws that we have on the federal books. So the states have had to pick up the slack. President Obama said he was pleased with the ruling and added that the US Congress must debate immigration. Obama said the "show me your papers" clause should have been wiped from the books. Republican Mitt Romney has toned down his immigration rhetoric as November's presidential election looms as both he and Obama court the Latino vote.