Further inquiries are to be carried out into whether detectives were told to limit a child abuse investigation centred on the former MP Lord Janner.
A home belonging to the 86-year-old peer, who was a Labour MP in Leicester for 27 years, was searched in 2013.
Last year it was reported that in 1989 a detective sergeant was told not to arrest Mr Janner or search his home.
The Independent Police Complaints Commission has said more investigation is needed into the claims.
Leicestershire Police said internal inquiries had been made before the matter was referred to the commission.Greville Janner was Labour MP for Leicester North West and then Leicester West between 1970 and 1997.