The United States Court of Appeals for the District of Columbia Circuit on Friday threw out a lawsuit by Sheriff Joe Arpaio of Maricopa County, who argued that President Obama’s executive actions on immigration were unconstitutional. The court upheld a district judge’s finding that the sheriff did not have grounds to sue. Sheriff Arpaio claimed his office had been injured by Mr. Obama’s 2014 order that was intended to ease the threat of deportation for about 4.7 million undocumented immigrants. Judge Nina Pillard, writing for a three-judge panel, said the sheriff’s predictions of more crime and an increase in the jail population “contradict acknowledged realities.”