Apparently taking a dig at the ministers, he said rationalist outfit Dravidar Kazhagam's chief K Veeramani has given a "beautiful idea of a lie detector test".
"Only if that method is used, many truths will come from the present ministers," he told reporters here when asked about contradictory claims of ministers over Jayalalithaa's 75-day hospitalisation and death on December 5 last year.
He said K Veeramani had said truths over Jayalalithaa's death should be brought out using the lie detector test.
Forest Minister Dindigul C Sreenivasan and Commercial Taxes Minister KC Veeramani had said none had seen Jayalalithaa during her hospitalisation.
Tamil Development Minister K Pandiarajan too had said he had never seen her during her hospitalisation.
However, ministers Sellur K Raju and Nilofer Kafeel contradicted them.
While Mr Raju said "all ministers saw her," Mr Kafeel had said she had once seen Jayalalithaa while she was shifted from one room to another in Apollo Hospital.
Not only state ministers, but several others who had visited Apollo Hospital here during Jayalalithaa's hospitalisation should be inquired on the issue, he said.
He listed Governor Ch Vidyasagar Rao, "ministers who came from Delhi, doctors of AIIMS Delhi and London doctor (Dr Richard Beale)," as those who should be questioned.
"To inquire them and bring out the truth, we (DMK) have been saying that only a CBI probe will do and we say that now as well," he said.
PMK chief Ramadoss too demanded a CBI probe on the matter and said chief minister Palaniswami and deputy chief minister O Panneerselvam should be questioned by the central agency.
Alleging that the ruling AIADMK regime was not interested in unearthing the "mystery," behind Jayalalithaa's death, he said "there is no use," of the inquiry commission set up to go into the matter.