PSNI chief constable Hugh Orde is to be confronted next week over claims that the police secretly bugged a Co Derry solicitor during confidential meetings with his clients.
Limavady solicitor Manmohan Sandhu is in police custody after he was arrested on Tuesday on suspicion of being a member of the loyalist Ulster Volunteer Force.
His solicitor has claimed that the arrest was based on evidence and intelligence gathered from covert listening devices planted at the Antrim Serious Crime Suite, which the police allegedly used to eavesdrop on Mr Sandhu's consultations with as many as 50 clients.
The Law Society of Northern Ireland is set to demand an explanation from Mr Orde when it meets him to discuss the matter next Monday.
Mr Sandhu's solicitor, Joe Rice, has already said that the alleged eavesdropping raises serious questions about police interference in the confidentiality of lawyer-client conversations.