Chennai, Jan 19: Tamil Nadu Governor RN Ravi on Thursday filed criminal defamation suit in a Chennai court against now suspended DMK leader Sivaji Krishnamurthy over his alleged defamatory remarks against the Governor. Krishnamurthy was suspended by the DMK days ago after he made allegedly critical remarks against Ravi in connection with him skipping portions of the government-prepared address to the state assembly. Tamil Nadu Raj Bhavan and the state unit of BJP had approached police with separate complaints, seeking action against the DMK functionary for his 'abusive and intimidatory' speech, targeting Ravi.