While the murder was executed on the night of 29th April 1999, and the two friends of Manu Sharma were arrested on 4 May, in the movie the friends are arrested in Oct. 1969 (the news channel flashes this date) way before the murder took place.
In one of the scenes shown in early 2006, Vidya Balan is seen getting off Indraprasth station on the metro. However, that station opened only in Nov 2006.
In one scene, Vidya Balan was entering a bus. The fare written on the bus is Rs.5, 10 and 15. But the fare was Rs.3, 7 and 10 at that time (shown in the movie). It was hiked in the year 2009.
In the scene where Meera Gaity is in a hospital, the board reads Fortis. It was only in late 2009 that Fortis came into existence after a takeover.