Delhi Police's Special Investigation Team (SIT) is expected to conduct a polygraph test on Congress leader Shashi Tharoor in connection with the death case of his wife Sunanda Pushkar, reports said on Tuesday. Earlier this month, polygraph test of six persons was conducted in connection with the high-profile murder case. Sunanda, who married Tharoor in 2010, had checked into The Leela Hotel in Chanakyapuri a day before her death on January 17, 2014.