A former chairman of The Bar Council of Northern Ireland has warned that citizens’ arrests by controversial “paedophile hunter” groups may be found to be unlawful.

The groups, which are increasingly prominent in Northern Ireland and sometimes alleged to be linked to loyalist paramilitaries, typically confront alleged paedophiles and tell them they are making a “citizens’ arrest”.

However, Mark Mulholland QC said citizens’ arrests can only be carried out in Northern Ireland in very limited circumstances, as set out in the Police and Criminal Evidence (NI) Order 1989.

These are where someone is witnessed or suspected of committing an indictable offence; the arrest is necessary, for example because they are causing injury to themselves or someone else; and it is not “reasonably practicable” for a constable to make the arrest.

Mr Mulholland told BBC Radio Ulster’s Good Morning Ulster: “Unless those three factors are present, there will always be question marks around the legality of what is happening here.”

He reiterated that “nobody is above the law”, adding: “By reason of that, we have a criminal justice system which ensures the presumption of innocence of any individual, with various safeguards and protections … because until and unless you’re convicted before a court, there must be fundamentally a presumption that you are otherwise not guilty.

“There may be arguments in due course, should cases come before the courts in instances where arrests of this nature have been effected, as to their lawfulness or otherwise.”