Former Delhi chief minister Arvind Kejriwal's counsel told the court that he could not come as he was already in custody.
Another accused in the case advocate Prashant Bhushan was present in the court during the hearing.
The court posted the matter for Aug 23.
Amit Sibal filed the defamation case against Kejriwal and his party members for tarnishing his image and reputation by making false statements.
He filed the case following May 15, 2013 press conference by Kejriwal, in which he alleged conflict of interest, saying Amit Sibal appeared in the Supreme Court for telecom firm Vodafone when his father was the minister of communications and information technology.
