Nen Ltd. v. Asiogu  14 NWLR (Pt. 1108) 582 at 593 paras. B-C, per Galadima, JCA:
“There are certain situations where a court of concurrent or co-ordinate jurisdiction can set aside the judgment or order of another court and such circumstances include where the writ or application was not served on the other party, or where the action is tainted with fraud or where the court lacks jurisdiction to entertain the action or is affected by debilitating defects that go to the root of jurisdiction.”
The rationale for the above decision is that service of court process, fraud and jurisdictional issues are issues the courts consider quite fundamental. Therefore, a court can set aside the judgment of another court of equal powers based on these grounds.
In applying the above principle, one must bear in mind that it is only appropriate for the special jurisdiction of certain courts to be considered. For instance, the National Industrial Court of Nigeria, Federal High Court and High Court of States have concurrent jurisdiction. To my mind, it would be improper to approach a Lagos High Court to set aside the Judgment of the National Industrial Court or Federal High Court even on those grounds.