Published Tuesday, 27 August 2013
The body of Mrs McConville, a mother-of-10 who vanished in December 1972, was not recovered for more than 30 years.
Her remains were finally found on Shelling Hill beach in Co Louth in 2003, but no one has ever been convicted over her death.
On Tuesday, the anniversary of Mrs McConville's body being found, lawyers for the family confirmed that they had been instructed to pursue civil action.
"The McConville family firmly believe that the RUC and subsequently the PSNI have utterly failed to assist the family's quest for the truth," Ciarán Mulholland, from J Mulholland & Co Solicitors, said.
"It is abundantly clear that police negligently failed to hold a prompt and efficient investigation into this matter."
The McConville family continue to mourn and grieve at the loss of their mother because they remain in the dark - their questions remain unanswered.
Ciarán Mulholland, family solicitor
According to the family's legal team, Mrs McConville was abducted by the PIRA on 30 November 1972 from a bingo hall in the lower Falls area of west Belfast.
They say she was interrogated on suspicion of being an informant before being found the next day, "roaming the streets in a state", by a British Army patrol who took her to Queen Street RUC barracks.
The lawyers further detail how Mrs McConville was then abducted from her home by the PIRA.
They claim numerous reports were made to the RUC, but "police still failed to act".
Mrs McConville is believed to have been tortured and murdered by her captors sometime in December 1972.
Mr Mulholland added: "The family now feel that, given the lengthy passage of time and the obstruction they continue to meet seeking the truth into the disappearance and murder of their mother, they have no alternative other than to hold the police and Ministry of Defence to account.
"Our clients' feel that legal action is now essential in their journey for truth, and accordingly, representations have been sent to both the Chief Constable and the Ministry of Defence."
An MOD spokesman said: "The MOD has and will continue to cooperate fully with all judicial processes.
"It would be inappropriate to comment further due to the ongoing civilian police investigation."
A PSNI spokesman said: "As this is a legal matter it would be inappropriate for us to comment."
© UTV News