Published Monday, 24 February 2014
Dissident republicans claimed responsibility for the murder of Mr Doherty. (© Presseye)
Mr Doherty was shot dead and his body found on the Braehead Road on 24 February 2010.
The Real IRA claimed responsibility for the 31-year-old's murder.
The father-of-one was from the Brandywell area of Derry and was due to get married three months after his death.
Detectives investigating the murder say they still need assistance and information from the community to make progress.
Police have carried out a number of searches and made three arrests but so far no one has been charged with Kieran's murder.
A spokesman for the PSNI's Serious Crime Branch, said: "This investigation remains open four years after this horrific murder.
"The investigation would make more progress if those individuals who know what happened to Kieran, and who killed him, would talk to us."
Kieran had been in the family home at Coshowen until about 8pm on the Wednesday evening of 24 February when he went out.
The next sighting of Kieran was when a passer-by found his body on the Braehead Road at around 10.40pm.
The spokesman added: "We want to speak to anyone who was on that road anytime from 8pm that evening and saw anything suspicious or who knows of Kieran's movements after he left his home.
"There has been speculation about Kieran's death but police need evidence to bring charges and get justice for Kieran and his family.
"Information from the community, not speculation, will help police to build an evidential case."
Anyone with information on what happened to Kieran Doherty is asked to contact police on 0845 600 8000.
Alternatively information about crime can be passed anonymously to the Crimestoppers charity on 0800 555 111.
© UTV News