9th Circuit Judges Michael Daly Hawkins, Ronald Gould and Richard Paez issued a 71-page joint opinion saying the president's order arrogates power that Congress reserved through legislation it passed.
A three-judge panel said, "For a third time, we are called upon to assess the legality of the president's efforts to bar over 150 million nationals of six designated countries from entering the United States or being issued immigrant visas they would ordinarily be entitled to receive".
Citing national security concerns, Trump announced his initial travel ban on citizens of certain Muslim-majority nations in late January, bringing havoc and protests to airports around the country.
"The Executive can not without assent of Congress supplant its statutory scheme with one stroke of a presidential pen", wrote the judges, all of whom are appointees of President Bill Clinton.
The three judges, all nominees of President Bill Clinton, said the travel ban exceeds the President's authority, calling it "an executive override of broad swaths of immigration laws that Congress has used its considered judgment to enact".
The D.C. -based appeals court dealt President Donald Trump a set back in trying to put an end to allowing transgender people - who suffer from proportionately higher rates of mental health issues - to enlist in the military, CBS News reported.
"It can not be in the public interest that a portion of this country be made to live in fear", the court wrote.
Department of Justice spokeswoman Lauren Ehrsam said in a statement, "We are pleased that the Supreme Court has already allowed the government to implement the proclamation and keep all Americans safe while this matter is litigated". The court said the ban should not be enforced against people with a relationship with a person or institution in the United States.
The lawsuit before the 9th Circuit was filed by the state of Hawaii, the Muslim Association of Hawaii and the association's imam, whose mother-in-law lives in Syria. That court heard oral arguments on the case en banc last month, just days after the Ninth Circuit.
The commander-in-chief is in charge of the U.S. Armed Forces, but doesn't have a say in who serves in the military.
In October, a federal trial court decision in Maryland ruled that Travel Ban 3.0, like its predecessors, violates the First Amendment's ban on religious discrimination. The legal battle over Trump's travel ban is likely to return to the Supreme Court soon - an outcome I thought likely ever since the Court dismissed as moot the cases involving Travel Ban 2.0, after that order expired.