"These parties had initially said Raja was not guilty. But they have now accepted his guilt, following his arrest," she told reporters.
Raja, who had allegedly manipulated procedures in the allocation of 2G spectrum, was arrested on Wednesday by the Central Bureau of Investigation.
Jayalalithaa was speaking after paying floral tributes to Dravida Munnetra Kazhagam founder C N Annadurai at his memorial on his 41st death anniversary.
Terming as 'artificial and well-planned' the arrest of Raja in 2G scam, Jayalalithaa said it was meant to 'hoodwink' the public and tell the Supreme Court that some action had been taken on the matter.
"The whole thing looks artificial and well planned. They should have done this long back," Jayalalithaa told reporters.
She said nothing short of a JPC to probe the scam was acceptable to her. The AIADMK leader said the government had adopted 'contradictory stands' on the issue.
Initially it said Raja was not guilty, but now it had arrested him and "in the process it not only became a laughing stock, but also made the public a laughing stock," she added.
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