Nov 20 (Reuters) - An Arizona police chief who calls himself "America's Toughest Sheriff" sued Barack Obama on Thursday soon after the U.S. president imposed sweeping immigration reforms, saying the changes were unconstitutional.
Maricopa County Sheriff Joe Arpaio, whose force used racial profiling during a crackdown on illegal migrants last year according to a judge, said Obama has overstepped his powers by bypassing Congress and bringing in the changes himself.
Arpaio's lawsuit said the reforms, which eased the threat of deportation for about 4.7 million undocumented immigrants, amounted to an amnesty and would encourage more people to cross the border illegally.
The biggest overhaul to immigration in a generation has set up a confrontation between the president and Republicans, who took full control of Congress this month and also said the president had gone too far by imposing the changes.
It was Obama's biggest use of executive actions in a year in which they have become his signature way of working around congressional gridlock.
"(Obama's immigration) programs are unconstitutional abuses of the President's role in our nation's constitutional architecture and exceed the powers of the President within the U.S. Constitution," read Arpaio's complaint filed in a federal court in Washington.
Obama earlier dismissed Republican accusations that the changes amounted to an amnesty for illegal immigrants.