Pakistan's Supreme Court said on Wednesday that a real estate tycoon could be in contempt of court for accusing the chief justice of turning a blind eye to his son's alleged corruption.
Riaz has not presented any examples of such verdicts and Iftikhar denies any wrongdoing.
Riaz's accusation "prima facie amounts to contempt of court for scandalising the court and bringing the court and the judges of the court into hatred, ridicule and contempt", the Supreme Court said in an order on Wednesday.
The case could damage Chaudhry, who became a household name in Pakistan and gained international recognition in 2007 after standing up to then President General Pervez Musharraf over his legally questionable bid to hold on to power.
It could also distract Pakistan from problems including a struggling economy, chronic power cuts and a Taliban insurgency.
Chaudhry has taken on the unpopular civilian government over allegations of corruption and challenged Pakistan's powerful military, demanding it produce suspected militants who were allegedly kidnapped and tortured.
The military, which has ruled the country for more than half of its 64-year history, denies wrongdoing.
Chaudhry, the one man with the clout to possibly keep the government and military in check, is unlikely to lose his job because the constitution provides strong protection for his office. He has dismissed criticism during hearings, saying he only acts to uphold the law and the constitution.
Riaz has accused Chaudhry of knowing that his son took bribes, and of not acting on the matter until last week, when the scandal broke, creating a media frenzy.
The Supreme Court also said Riaz's statements appeared to be "causing obstruction in the administration of justice because of the pendency of his cases in the court".
Riaz was summoned by a three-judge panel to explain his position on Thursday. He was not immediately available for comment.