The judge said that the Attorney-General of the Federation should be careful in using the report presented to him by the illegal panel.
The panel was set up by the Inspector-General of Police to investigate the allegations of violence and malpractice in the election.
The judge gave the judgement on Tuesday, May 5.
"Section 4 of the police act allows the police to set up such a panel to carry out investigations, the section does not however, state that the police can carry out such an investigation with apparatus outside the force," he said.
He said the Attorney-General of the Federation, Abubakar Malami should be careful in using the report presented to him by the illegal panel.
Justice Kolawole, however, rejected the prayer by the plaintiff asking him to squash the report of the panel.
The judge said he could not take action on the report because it was not before him, adding that the panel had already submitted its report to the attorney-general.
According to him, if it report contains useful information, it could be useful if turned over to a proper body under the law.
Governor Nyesome Wike and the Rivers government had asked the court to nullify the outcome of police investigation into the violence that characterized the election.
The police panel, which also had personnel of the DSS as members, was chaired by Damian Okoro, a deputy commissioner of police.