Rao was an MLA in the Haryana assembly for four terms, beginning in 1977. From 1982 to 1987 he was a provincial Minister of State responsible for Food and civil supplies.[8]
He was elected to the Lok Sabha as a Member of Parliament in 1998, serving in the parliaments of 1998 - 1999, 2004 –2009, 2014 - 2019, 2019 - 2024, 2024 - 2029. From 1991 to 1996 he served as Cabinet Minister for the Environment, Forest, Medical and Technical Education, then as Minister of State for External Affairs (2004–2006) and as Minister of State for Defense Production from 2006 to 2009. He was the chairman of Parliamentary Information technology committee since 2009.
Rao Inderjit Singh was a member of the Indian shooting Team from 1990 to 2003 and won a Bronze Medal at the Commonwealth Shooting Championship. He was also a National Champion in Skeet for three consecutive years and won three gold medals in the SAF Games.[13]
Controversies
Against Bhupinder Singh Hooda
Rao Inderjit Singh, who hails from South Haryana, alleged that the Haryana Chief Minister Bhupinder Singh Hooda was developing his own constituency Rohtak at the cost of other parts of the state. He presented the data procured through RTI to support his allegation: Out of a total of 5,135 announcements of schemes in Haryana, 2,045 were for the three districts of Rohtak, Jhajjar and Sonepat that comprise areas of Hooda's own constituency and that of his son Deepender Singh Hooda. Of the 3,356 completed schemes, 1,560 were from these three districts.[14][15] On 23 September 2013, he resigned from Congress.[16]