Tommy Robinson told police "not a chance bruv" when they demanded he hand over the pin to his mobile at the Channel Tunnel, a court heard.
He said he would not give up his phone's Pin because it had "journalistic material" on it, Westminster Magistrates' Court heard on Monday.
The political activist, who had more tha £13,000 and 1,900 euros in cash with him, told officers he was driving his silver Bentley to Benidorm for a couple of days when he was stoppd by officers, his trial was told.
Police became suspicious of the far-right activist’s "vague replies" about what he was doing and demanded access to his iPhone under Schedule 7 of the Terrorism Act.
Asked to give access to the iPhone, Robinson replied: "Not a chance bruv," prosecutor Jo Morris said.
"It's my work, I'm a journalist," he said, adding that it held information about "vulnerable girls".
"The process by which journalistic material would be protected was explained to him," Ms Morris told the court.
Robinson was later charged under the Terrorism Act 2000.
Under schedule 7, police are allowed to stop anyone passing through a UK port “to determine whether they may be involved or concerned in the commission, preparation or instigation of acts of terrorism”.
The person who is detained can be held for up to six hours, is legally obliged to answer questions and must provide the password or Pin for electronic devices.
If they refuse, they can be charged with terror offences.
Robinson, 42, is standing trial at Westminster Magistrates’ Court on Monday, aftrer refusing to hand over his pin.
The defendant, whose real name is Stephen Yaxley-Lennon, was stopped at the Channel Tunnel in July 2024 after police officers had concerns about his demeanour, Westminster Magistrates' Court heard.
The officers, who asked about his reasons for travelling, felt his behaviour, under their guidelines, met criteria for a possible link to terrorist activity or future terrorist activity, prosecutor Jo Morris said. They also noted his notoriety as a political activist.
Pc Mitchell Thorogood, of the Channel Tunnel policing team, told the court Robinson arrived on the day to buy his tickets rather than booking in advance, which he said was "unusual".
He was also travelling in a high-value car that was not registered under his name, the trial heard.
Robinson, whose real name is Stephen Yaxley-Lennon, was detained and responded by recording a voice note on his phone and began to film the officers, the court heard.
The trial continues.
