He represented M. Moorthy's widow, Kaliammal Sinnasamy in a legal tussle over the late Everest conqueror's body.
[4] The news of his victory was one of the surprising ones in the 2008 elections as he is being detained under the Internal Security Act without trial after organising anti-discrimination protests.
Manoharan along with four other lawyers, P. Uthayakumar, P. Waytha Moorthy, K. Ganghadaran and V. Ganabatirau are seeking justice for the Hindu and Indian Malaysian community.
On 30 October 2007, Manoharan, P. Uthayakumar, P. Waytha Moorthy and S. V. Ganapathi Rao were arrested for taking part in the 2007 HINDRAF demonstration against the demolishment of a Hindu Shrine in Kuala Lumpur.
[5] Manoharan was also part of a team of lawyers representing P. Uthayakumar, P. Waytha Moorthy and S. V. Ganapathi Rao after they were arrested again for sedition.