Former telecom minister Dayanidhi Maran and his brother Kalanithi Maran must face trial in what is known as the illegal telephone exchange case, the Supreme Court today said, confirming a High Court order that set aside their discharge in March. "The allegation is you have used phones for your brother's TV. You face the trial," the Supreme Court said, dismissing Dayanidhi Maran's appeal in the decade-old case.