A Conservative activist at the centre of bullying allegations was appointed to a key role in the party's general election campaign despite warnings of his record of "aggressive and bullying conduct", an inquiry has found.
Law firm Clifford Chance found that complaints were made about the conduct of the so-called "Tatler Tory" Mark Clarke on seven occasions before the party finally mounted an investigation into his behaviour.
However the report said that the party's then co-chairmen Lord Feldman and Grant Shapps had not been made aware of allegations until August last year when an internal party inquiry was launched.
The law firm was finally brought in to investigate after the suicide of a young activist Elliott Johnson whose complaint against Mr Clarke finally triggered the internal investigation.
In response to its report, the party said it was establishing new procedures for handling complaints by volunteers, including a dedicated hotline and training for relevant party employees.
Party chairman Sir Patrick McLoughlin said: "The death of Elliott Johnson was a tragedy and our thoughts remain with his family and friends.
"As we address the findings of this report I want to make clear that there can be no place for bullying behaviour in our party and we all have a responsibility to act when it occurs.
"The actions we are taking today will continue to ensure that volunteers, who are so vital to our party, can flourish."