Amid unusually tight security, Osama bin Laden’s son-in-law will go to trial on Monday, charged with conspiring to kill Americans in his role as al-Qaida’s mouthpiece after the 11 September 2001 terrorist attacks.

Spectators at the trial of Suleiman Abu Ghaith, the highest-ranking al-Qaida figure to face trial on US soil since the attacks, will pass through a metal detector before entering a Manhattan courtroom where prosecutors will try to prove to an anonymous jury that the one-time terror-network spokesman tried to rally others to kill Americans.

Prosecutors say they plan to show jurors during their opening statement a picture of Abu Ghaith seated with Bin Laden and other al-Qaida leaders on the day after 11 September 2001, as they make statements about the attacks. They say Abu Ghaith described the circumstances of the filming in his post-arrest statement.

Also during the trial, prosecutors will show jurors post-September 11 videos in which the charismatic bearded man promises more attacks on the United States as devastating as those that demolished the World Trade Centre.

“The Americans must know that the storm of airplanes will not stop, God willing, and there are thousands of young people who are as keen about death as Americans are about life,” Abu Ghaith said in a 9 October 2001 speech.

In one widely circulated propaganda video, Abu Ghaith can be seen sitting with Bin Laden and the current al-Qaida leader, Ayman al-Zawahiri against a rocky backdrop.

Defence lawyers for the balding and bearded defendant are offering some surprises in the case, including an assertion last week that some of the government’s evidence relates to a detainee at Guantánamo Bay with a similar name to Abu Ghaith rather than to the defendant who has pleaded not guilty. US District Judge Lewis A Kaplan on Friday called the mistaken identity claim “utterly meritless.”

Abu Ghaith’s attorneys are also trying to enlist help from professed September 11 mastermind Khalid Sheikh Mohammed to bolster the case for acquittal, though it has not come fast enough for them to gain permission from Kaplan for Mohammed to testify, perhaps through a video link to Guantanamo Bay. If convicted, Abu Ghaith could face life in prison.

Defence attorneys said on Friday that Mohammed had provided a 14-page response to written questions, but his lawyer was refusing to turn it over unless there was a guarantee that military lawyers at Guantanamo would not review it. The judge refused to consider the matter further.

The Kuwaiti-born defendant was flown to the United States a year ago from Jordan, where he was captured as he headed to Kuwait, which had revoked his citizenship after the September 11 attacks.

In an affidavit filed last year as he tried to suppress a 22-page statement he made to authorities, Abu Ghaith said he left Afghanistan in 2002 and entered Iran, where he was arrested and held in prisons and interrogated extensively.

Abu Ghaith said he was released from Iranian custody on 11 January 2013, when he entered Turkey, where he was detained and interrogated before his release on 28 February 2013. He said he was heading home to Kuwait on a plane to see family when the flight landed instead in Amman, Jordan, where he was handcuffed and turned over to US authorities.

Abu Ghaith is married to Bin Laden’s eldest daughter, Fatima, one of nearly two dozen children Bin Laden was believed to have fathered before he was killed in Pakistan by US Navy Seals in 2011.

Before heading to Afghanistan in 2000, Abu Ghaith was an imam at a Kuwaiti mosque and taught high school religion classes until 2000.

When he was brought to the United States for trial, some criticised the move, saying al-Qaida leaders should not receive the protections offered by a civil court trial. But numerous pre-trial hearings have gone on without a hitch in a courthouse that has featured more than a half dozen major al-Qaida-related terrorism trials over the last two decades stemming from the 1993 World Trade Centre bombing, a 1993 plot to blow up New York City landmarks including the United Nations, the deadly 1998 bombings of two US embassies in Africa, and a plot to blow up a dozen US airliners over the Far East in 1995.

The attorney general, Eric Holder, announced in November 2009 that Mohammed would be tried in federal court in New York City over the September 11 attacks, but the decision was reversed months later after city officials complained that the trial would impose large security costs on the city and be disruptive to the local economy.