Prince Harry could be banned from entering the US by a border guard who has read that he has taken drugs

Prince Harry could be banned from entering the US by any border official who knew about his drug-taking admissions in his autobiography, legal experts have claimed.

The border officials might laugh at him about the admissions if he hadn’t indicated it on his visa application form.

It means the Duke of Sussex could be held back from returning to the US next month after his trip to London, where he is suing Mirror Group newspapers over phone hacking allegations.

The revelations come after it emerged that the US government will appear in federal court next Tuesday to answer questions about Harry’s visa application after he admitted using cocaine, cannabis and magic mushrooms.

Washington DC-based think tank The Heritage Foundation is suing the Joe Biden administration to force officials to release the duke’s immigration files.

Raymond G. Lahoud, an immigration attorney with Norris McLaughlin, told DailyMail.com that Harry could be banned from entering the US if he encounters the wrong border guard.

A CBP officer would not be able to question Harry about his past drug use if he had stated it at the time of his visa application, as a decision to issue a waiver would have already been made.

It is unknown whether Harry stated this.

“Every time he enters the US, he has to go through Customs and Border Protection (CBP),” Lahoud said.

“Anyone would get those questions and would be rejected if there is a clear record of drug use [that has not previously been declared].

‘Being a customs broker, I have the right to answer any questions I want. If he has broken any law related to drug use, that is grounds for disqualification, whether or not there is a conviction.”

Mr Lahoud added that he thought it unlikely that this would happen even if Harry had not reported his drug use because he was not a ‘normal citizen’ – agreeing with The Heritage Foundation’s claim that he was ‘a got special treatment because it’s Prince Harry.”

The think tank argues that an explanation of how Harry entered the US – despite later admissions of drug use – is in the public interest.

It also wants to know how Harry answered questions about his drug use on his application.

The case will be heard before a federal judge in the U.S. District Court for the District of Columbia on June 6 at 2:30 p.m.

It comes after the think tank failed to make the application public in March using freedom of information laws.

Mr Lahoud said the case could ‘go either way’ but added that he thought the privacy of immigration data would trump the public interest argument – and that the files would not be released.

He did say, however, that there is a risk that the publicity generated by the lawsuit would leave a “major mark” on Harry’s immigration file, making it more difficult for him to renew his visa.

Mr Lahoud said if it turns out that the duke failed to mention his drug use on his visa application, it “should be withdrawn”.

In Spare, Harry revealed that he first used cocaine on a shooting weekend at the age of 17. On other occasions, he did “a few more lines.”

He also admitted to hallucinating at a celebrity-filled event in California and smoking cannabis after his first date with Meghan.

And the Duke spoke of his “positive” experience with the psychedelic drug ayahuasca, saying it “gave me a sense of relaxation, liberation, comfort, a lightness that I could hold on to for a while.”

Harry made the comments in an interview with therapist Dr Gabor Maté, an outspoken proponent of drug decriminalization who has reportedly used Amazonian ayahuasca to treat patients with mental illness.

Harry told him, “(Cocaine) didn’t do anything for me, it was more of a social thing and definitely made me feel like I belonged, I think it probably also made me feel different than I felt, which was kind of the point.

“Marijuana is different, that really helped me.”

It’s unknown what kind of visa Harry has, but it could be a temporary non-immigrant visa called an O-1 for extraordinary ability, which would expire after five years.

Under US law, non-citizens who admit to using drugs illegally or have been convicted of drug offenses may be banned from entering the country.

If they admit this, a waiver will likely be required to gain access, but this can be a difficult and lengthy process.

This may include undergoing a medical examination, including blood and urine tests, a chest X-ray, and an interview to confirm that the applicant is off drug use.

Kaitlyn Daviesfrom specialist immigration firm Davies Legal, said it could take ‘months’ for a waiver to be granted, but it is unlikely to be tested ‘because the admission to drug use does not appear to be recent use’.

She also said Harry could get into trouble at border control.

“Formally confessing to cocaine use, without exceptional circumstances, will likely prevent Harry from ever becoming a green card holder or US citizen,” she told DailyMail.com.

“While the confessions in his book would not be ‘formal,’ an interviewing officer could make them formal by interrogating him in some way about his drug use claims.”

Amy Winehouse was denied a US visa in 2008 due to her well-documented drug addiction, which led her to cancel plans to attend the Grammy Awards.

Kate Moss is also said to have had US visa problems in the past after images surfaced in 2005 of her sniffing a white powder – presumably cocaine.

She did go to the US in 2009 to attend the opening of a new Topshop store in New York.

Nile Gardiner, director of the Margaret Thatcher Center for Freedom at The Heritage Foundation, released details of the pending case on Monday.

Earlier this month, Mr. Gardiner – a former senior aide to former Prime Minister Margaret Thatcher from 2000 to 2002, who advised her on international policy issues – said the lawsuit focused on “transparency and accountability.”

“It is a clear public interest in the US to ensure that Harry does not receive favorable or preferential treatment from the immigration authorities,” he added.

“Any discrepancy between the details in his immigration application and the revelations about drug use in Spare would have serious consequences for his legal status in the United States.

“Harry should welcome the release of his immigration application so that the public can see what has been put in the application.”

DailyMail.com has reached out to Harry’s representatives for comment.