Lorraine McCausland was returning from a night out when she was beaten to death. Her body was found dumped near a stream in Ballysillan not far from the local drinking den she had been in.The main suspect in her killing was a leading member of the UDA.An investigation by the Historical Enquiries Team in 2009 couldn't confirm collusion, but they did tell the family that, while the main suspect was not an informer in March 1987 when Lorraine was murdered, he was by April 1987.The Police Ombudsman is now reviewing claims by the family that police did not do enough to find her killers.At the request of her family, Dr Nat Cary - who has worked on cases such as Ian Tomlinson's, who was attacked by police in a G20 protest in London, and the murders of Soham schoolgirls Holly Wells and Jessica Chapman - has reviewed the murder investigation.He believes she may have been raped by her murderer.Dr Cary asked why police, in his words "so readily accepted consensual sexual activity" in the case, which could have been "rape or attempted rape".Questioning some of the findings of the post-mortem examination, he also concluded there "may still be some forensic opportunities".Dr Cary's letter is being sent to the PSNI, as the family's solicitor Padraig O'Muirigh believes there is now compelling case to reopen the police investigation."This is one of the most tragic cases over the course of the last 40 years and in my view it's one of the most shameful police investigations in that period as well," he told UTV."Despite the forensic opportunities, despite the fact that the dogs in the street seemed to know who was involved with this murder and other linked murders, there have been no convictions to date. Hopefully a new investigation will change that."