Kanimozhi, has been named as co-accused and been chargesheeted by the CBI for allegedly accepting a Rs 214 crore bribe that was a part of India's largest swindle, the 2G scam. Hence, on the other part, the Congress party made it very clear that there wouldn't be any stop in the legal process against kanimozhi.
The Union health minister Ghulam Nabi Azad, who met Karunanidhi at his hotel in New Delhi said, "Our leader Sonia Gandhi is concerned because Kanimozhi being a woman is in jail and it is a matter of concern. But the fact is that one cannot do anything."
The above mentioned statement again highlights the fact that Congress, on one hand, needs the support of DMK's 18 members in Lok Sabha, does not wish to terminate the tie-up with Karunanidhi. On the other hand, it would keep a safe distance from its partner involved in 2G scam.
Also, party spokesperson Manish Tewari's statement that people should refrain from trying "to politicize a tragedy of the proportions which are undefinable" shows that Congress doesn't want to swap partners in Tamil Nadu as Jayalalithaa tried to drive a wedge between Sonia and Karunanidhi by reviving the allegation of DMK's links to Rajiv Gandhi's assassination in 1991.
Hence, Karunanidhi derived sympathy and comfort as Congress showed its concern towards DMK by blocking Jayalaltha's offensive over DMK's alleged link to Rajiv Gandhi's killing.
The Congress - DMK relationship is driven by mutual compulsions, which seem to make it more durable at present. While the Dravidian party needs a power perch at the Centre to face a vindictive Jayalalithaa, UPA also requires DMK's 18 MP's to stay comfortable in the Parliament.