Dozens of Turkish lawyers arrested 18 months ago have been subjected to ‘excessively punitive’ treatment by state authorities, with 15 of the 46 still detained in prison, an international delegation of lawyers reports.

The trial of the 46 has been consistently delayed, with three-month gaps between one-day hearings, ‘causing extreme trauma to the lawyers and their families’, the delegation says.

This miscarriage has been compounded by the arrest of a further 50 lawyers, who last month were arrested and assaulted by police for taking part in a peaceful demonstration, the delegation adds.

The 46 lawyers face prosecution for being members of an illegal organisation, allegedly in the course of undertaking their professional duties as defence lawyers for Abdullah Ocalan, the imprisoned leader of the Kurdistan Workers’ Party (PKK). Ocalan is serving a life sentence for treason.

The delegation found that the authorities had violated international standards, including seizing client files, tapping phones, intercepting emails and relying upon a witness statement made under police duress. The lawyers had also been denied the opportunity to present their defence and their hearings repeatedly delayed.

This is not only a breach of the UN Declaration on the Rights of Lawyers, the delegation contends, but is also ‘excessively punitive’ to both the lawyers and their families, with some 15 of the original 46 lawyers still in prison.

The fifth and most recent hearing was on 20 June and the next will be on 17 September, another three-month delay.

Some 50 more lawyers were detained on 11 June for taking part in a protest during the Taksim Square unrest over the planned development of an Istanbul green space. They were reportedly beaten during the police intervention, but were released when 100 lawyers gathered outside the police station to demand their liberty.

The delegation comprised lawyers from the UK, France, Germany and other European countries.