A man wrongly imprisoned on terrorism charges is demanding to know why two police officers were not prosecuted for perjury, the High Court has heard.
John Boyle, 45, was jailed for 12 years in 1977. The Belfast man was released in 1986 after his case was reviewed.
His conviction was quashed by the Court of Appeal in April 2003 when scientific analysis revealed that notes of one of his interviews had been rewritten.
Mr Boyle wants the DPP to explain why the officers involved were not charged.
The man, from the Markets area of Belfast, was jailed on charges of having a firearm with intent and being a member of a proscribed organisation.
After the Criminal Cases Review Commission investigated his case, he was freed, having served nine years in prison.
His conviction was quashed in the Court of Appeal in 2003.
Police Ombudsman Nuala O'Loan had recommended prosecution of the two officers who interviewed Mr Boyle.
However, the DPP said there was "insufficient evidence" to obtain a conviction.
In court on Monday, a lawyer for the DPP argued that detailed reasons for the decision did not have to be given.
Mr Boyle's legal action is aimed at discovering how the DPP reached its conclusions and wants a full explanation.