On June 26, 2018, the U.S. Supreme Court upheld the third Executive Order (Presidential Proclamation 9645) and its accompanying travel ban in a 5–4 decision, with the majority opinion being written by Chief Justice John Roberts.

[29] Trump's press secretary Sean Spicer cited these existing restrictions as evidence that the executive order was based on outstanding policies saying that the seven targeted countries were "put (...) first and foremost" by the Obama administration.

[58][59] On September 4 vice presidential candidate Mike Pence defended the Trump–Pence ticket's plan to suspend immigration from countries or regions of the world with a history of terrorism on Meet the Press.

[71] In January 2016, the Department of Justice (DOJ), on request of the Senate Subcommittee on Immigration and the National Interest, provided a list of 580 public international terrorism and terrorism-related convictions from September 11, 2001 through the end of 2014.

[80] Nowrasteh notes 40 of the 580 individuals (6.9%) were foreign-born immigrants or non-immigrants convicted of planning, attempting, or carrying out terrorist attacks on U.S. soil (his analysis does not specify whether any, some, or all 40 are from the six or seven countries specified by executive orders 13780 or 13769).

"[81] The New York Times said that candidate Trump in a speech on June 13, 2016, read from statutory language to justify the President's authority to suspend immigration from areas of the world with a history of terrorism.

[83] According to CNN, the executive order was developed primarily by White House officials (which the Los Angeles Times reported as including "major architect" Stephen Miller and Steve Bannon[84]) without input from the U.S. Department of Justice's Office of Legal Counsel (OLC) that is typically a part of the drafting process.

[99][100] The committee, which included former U.S. attorney general and chief judge of the Southern District of New York Michael Mukasey and representatives Mike McCaul and Peter T. King, decided to drop the religious basis and instead focus on regions where, as Giuliani put it, there is "substantial evidence that people are sending terrorists" to the United States.

[108] Section 3 of the order blocks entry of people from Iran, Iraq, Libya, Somalia, Sudan, Syria, and Yemen, for at least 90 days, regardless of whether or not they hold valid non-diplomatic visas.

[114] Citing Section 3(c) of the executive order, Deputy Assistant Secretary of State for Consular Affairs Edward J. Ramotowski issued a notice that "provisionally revoke[s] all valid nonimmigrant and immigrant visas of nationals" of the designated countries.

[130] Early Saturday, January 28, the Department of Homeland Security's acting press secretary Gillian Christensen said in an e-mail to Reuters that the order barred green-card holders from the affected countries.

[133][134] On January 29, Secretary of Homeland Security John Kelly deemed entry of lawful permanent residents into the U.S. to be "in the national interest" exempting them from the ban according to the provisions of the executive order.

[133][135] On February 1, White House counsel Don McGahn issued a memorandum to the heads of the departments of State, Justice, and Homeland Security clarifying that the ban-provisions of the executive order do not apply to lawful permanent residents.

[6] The only suggested component of the uniform screening procedure in section 4 that specifically mentions a potential entrant's mindset is "a mechanism to assess whether or not the applicant has the intent to commit criminal or terrorist acts after entering the United States".

[142] The Trump administration has formally proposed adding optional collection of social media account information for visa applicants from China affecting approximately 3.6 million people annually.

[146] Part (b) of Section 4 requires the departments of State and Homeland Security, the Director of National Intelligence, and the FBI to present progress reports on the uniform screening procedure to the President, the first of which is due 60 days from the date the order was issued.

[151] An internal report compiled by the U.S. Department of Homeland Security Intelligence and Analysis Unit, however, concluded that people from the seven nations affected by the travel ban pose no increased terror risk.

"[153] Experts on terrorism, such as Charles Kurzman of the University of North Carolina, Brian Michael Jenkins of the RAND Corporation, and Daniel Benjamin of Dartmouth College, formerly the State Department's top counterterrorism official, all commented upon the order.

"[154] According to The New York Times reporter Scott Shane, the seven countries in the executive order had a "random quality"; the list excluded Saudi Arabia and Egypt (where many jihadist groups were founded) and Pakistan and Afghanistan (where extremism has a long history, and which have "produced militants who have occasionally reached the United States").

The New York Times reported people with various backgrounds and statuses being denied entry or sent back; this included refugees and minority Christians from the affected countries as well as students and green-card holders returning to the United States after visits abroad.

[175] The New York Times reported that 86,000 nonimmigrant-temporary visas (mostly for tourism, business travel, temporary work, or education) have been granted to citizens in the seven affected countries in the 2015 fiscal year.

[179][180] However, Committee for Economic Development CEO Steve Odland[181] and several other executives and analysts commented that the order will not lead to significant changes in IT hiring practices among US companies, since the countries affected are not the primary source of foreign talent.

[182][further explanation needed] According to the Hill "a cross-section of legal experts and travel advocates" say that the order "could have a chilling effect on U.S. tourism, global business and enrollment in American universities".

[255] Google co-founder Sergey Brin (who emigrated to the United States with his family from the Soviet Union at the age of five)[256] and Y Combinator president Sam Altman joined the protest at San Francisco airport.

[267] Under the new policy, citizens from Libya, Syria, Iran, Somalia, Yemen and Sudan would be banned from entering the U.S. if they couldn't prove that they have a "bona fide relationship" with families in America, which excludes grandparents, aunts, uncles or any other "distant relatives.

[278] According to the DHS inspector general, U.S. Customs and Border Protection officers then violated the court orders by continuing to prevent some foreign passengers from boarding flights bound for the United States.

Additionally, fifteen Democratic state attorneys general released a joint statement calling the executive order "unconstitutional, un-American and unlawful", and that "[w]e'll work together to fight it".

[288] On February 9, two days after hearing argument, a panel of the United States Court of Appeals for the Ninth Circuit unanimously denied the request for a stay of Judge Robart's temporary restraining order.

[306][307] According to an administration official, a redraft version of the executive order will focus on the same seven countries minus Iraq,[308] but exempt lawful permanent residents and those who already hold visas, whether or not they have entered the United States.

Judge Watson stated in his ruling, "When considered alongside the constitutional injuries and harms discussed above, and the questionable evidence supporting the Government's national security motivations, the balance of equities and public interests justify granting the Plaintiffs.