A French publisher was interrogated by British police under counter-terrorism laws about his support for Emmanuel Macron and anti-government authors before his arrest, claims his lawyer. Ernest Moret, 28, who arrived in London on Monday evening to attend a book fair, was arrested on counter-terrorism charges in the early hours of Tuesday morning when he refused to disclose the passcodes to his confiscated iPhone and Macbook. His lawyer, Richard Parry from Saunders solicitors, accused the UK authorities of an “abuse of power” in their treatment of Moret. Parry, who was present during one of Moret’s police interviews, said Moret was asked if he supported the French president. He was also asked whether he attended demonstrations in France against Macron’s controversial pension plans, Parry stated. And he was invited to name anti-government authors in the catalogue of La Fabrique, the radical publishing house he works for as foreign rights manager. He refused to answer all these questions. Parry has demanded full disclosure of any involvement of the French authorities in Moret’s arrest, as questions were asked in the National Assembly in France about Moret’s treatment. Moret was released on bail on Tuesday, but his iPhone and Macbook remain in the hands of officers. He has been ordered to report to the police in four weeks. Parry said: “He is here to attend a book fair. What legitimate interests is it for British police to ask about his attendance at demonstrations in France?” He added: “They were interested in whether he had extremist material on his laptop and whether he had written anything about the recent protests in France.” Parry is concerned that the French security services asked their British counterparts to use counter-terror powers that are not available in France to confiscate electronic devices. “If the British police did this on behalf of a foreign power, because that foreign power is unable to do the same to its citizens, how is that proper use of terrorism legislation? If the only reason for this was mutual assistance for the French, we think it’s an abuse of process.” He added: “We need truthful answers from the French authorities about their involvement. We raised this on the record in Ernest’s interview. We suspect this is an intelligence gathering operation, and that the British will just pass the intel [gathered from his phone and laptop] on to the French.” Parry was also alarmed that Moret was asked to supply information about his contacts. “They can use these powers to effectively stop publishers and journalists from doing their work,” he said. La Fabrique and the British publisher Verso released a new statement on Wednesday condemning Moret’s treatment as “chilling”. It added: “This case sets a precedent for anyone who does intellectual work and whose output may be deemed inconvenient by those in power.” It demanded the dropping of all proceedings against Moret and the return of his phone and laptop. The Metropolitan police has been approached for comment.