NEW YORK/SAN FRANCISCO (Reuters) - Liberal U.S. Supreme Court justices sought assurances on Wednesday that the Trump administration’s policy for granting medical or other exceptions to a ban on travelers from several Muslim-majority countries amounted to more than window dressing.

A protester holds a placard outside the U.S. Supreme Court, while the court justices consider case regarding presidential powers as it weighs the legality of President Donald Trump's latest travel ban targeting people from Muslim-majority countries, in Washington, DC, U.S., April 25, 2018. REUTERS/Yuri Gripas

Immigration attorneys and visa applicants from countries covered have complained about the scarcity of waivers granted and the lack of transparency around a process intended for applicants with serious medical needs or significant personal and business ties to the United States.

The four-month-old ban, Republican President Donald Trump’s third attempt to restrict travel from countries he says pose a threat, is the latest to face court challenges. It covers Iran, Libya, Somalia, Syria and Yemen along with North Korea and some officials from Venezuela.

Chad was recently dropped from the list.

Three liberals on the nine-member court signaled concern about the waivers in their questioning. The issue was not raised by any of the court’s five Republican-appointed members, who indicated an unwillingness to second-guess Trump on the national security justifications offered for the policy.

Liberal Justice Stephen Breyer asked U.S. Solicitor General Noel Francisco, representing the administration, for assurances the waiver process was more than “window dressing.” Breyer cited the slim number of waivers that have been issued.

Justice Sonia Sotomayor, who also referenced “window dressing,” asked, “What are you personally doing to represent to us that it is, in fact, a real waiver process?”

Francisco said he was unsure how well the process was publicized but said he suspected applicants understood it.

“State Department consular officers automatically apply the waiver process in the course of every visa application,” Francisco responded. “They are doing that.”

A third liberal, Justice Ruth Bader Ginsburg, asked about a child with cerebral palsy who was denied a waiver.

The government’s brief to the Supreme Court said that more than 430 applicants had been cleared for waivers between Dec. 8, 2017, and April 1, 2018. But the State Department has refused to provide the number of visa applications submitted from the affected countries during that same period.

In March, Reuters reported that numbers provided to Congress showed there had been 8,400 applications for non-immigrant and immigrant visas from the banned countries from Dec. 8 through Jan. 8. If that rate of applications continued in subsequent months it would mean fewer than 2 percent of applications have been granted waivers.

A State Department spokeswoman declined to say why it would not provide numbers for visa applications from the banned countries.