Cotu yesterday sought to privately prosecute six senior officials over the development of Tassia II settlement scheme.
In an application filed at the Milimani law courts, Cotu wants to prosecute former NSSF acting managing trustee Richard Langat, trustee chairman Adan Daud, Finance secretary Mutua Kilaka and Labour PS Ali Ismail.
The Director of Public Prosecutions recommended closure of the file, saying there was no evidence of criminal culpability by the trustees.
The DPP said there was nothing to warrant criminal prosecution or administrative action against the officials in connection with the scheme.
The Ethics and Anti-Corruption Commission had also recommended the file be closed.
It said, however, administrative action should be taken against Langat for exposing NSSF to contractual obligation when all funds to finance the project had not been collected from the tenants.
Cotu secretary general Francis Atwoli also wants prosecution of Mutemi Nzetu and Gideon Kioko, members of the tender committee.
He says the board approved the Tassia II development for Sh5.3 billion. China Jiangxi International is the contractor.
Atwoli says by approving the project, the officials violated basic procurement rules and regulations.
He says in exonerating the board and the management staff, the DPP failed to consider the circumstances in which the tender was awarded and approved on the same day.