Justice V Bharathidasan granted the relief to the South Chennai District Secretary of AIADMK when the matter came up.
The threat was allegedly issued after Pannerselvam revolted against the AIADMK leadership last month.
Police had registered a case against Kalairajan for the alleged offences under IPC Sections 504 (intentional insult with intent to provoke breach of the peace) and 506 (punishment for criminal intimidation).
Kalairajan had moved the high court, claiming that he was innocent.