The Supreme Court recently observed that a challenge to a decree that is a 'nullity' can be set up at any stage, including the stage of execution. "It is well settled that if a decree is a nullity, its invalidity can be set up whenever and wherever it is sought to be enforced, even at the stage of execution as held in Kiran Singh and others vs. Chaman Paswan and others (1954 INSC 45).",...