"This is religious discrimination on its face," said LAX protester Keith James. "We don't want to be living in a society where people are discriminated against, because of their religion - Muslim or any other religion or no religion at all."
The ban was scaled back from Trump's original proposal in January, but is still considered highly controversial.
The new rules tighten restrictions on visas for citizens from six Muslim-majority countries: Syria, Sudan, Somalia, Libya, Iran and Yemen. The restrictions last for 90 days for most applicants, but 120 days for refugees.
The Supreme Court on Monday allowed the revised ban to take effect, as long as it exempts travelers who could prove a "bona fide relationship" with a U.S. person or entity.
The court offered only broad guidelines, but the Trump administration has defined that term as a parent, spouse, child, son-or daughter-in-law, sibling, parent-in-law or fiance. Other relationships will be reviewed on a case-by-case basis.
Los Angeles City Attorney Mike Feuer, who was at LAX Thursday, said he was concerned with how the federal government was defining the bona fide relationship.
"I am extremely concerned that the State Department has interpreted the Supreme Court's ruling in a way that is far too narrow," Feuer said.
Attorney Talia Inlender was among legal experts at a legal-aid desk at the Bradley International Terminal to help answer questions and ensure that people are not wrongfully detained.
She argued that the definition of bona fide relationships should be expanded.
"Many people are fleeing along with their families for the first time and seeking safety here and those people do have established relationships with refugee resettlement agencies, which we think clearly qualify as entities under the Supreme Court's order," Inlender said.
The state of Hawaii has also filed a court challenge to the definition of bona fide relationships.
The Supreme Court is expected to hear arguments on the travel ban in the fall.