Yvonne was shot dead in broad daylight whilst trying to police a protest outside of the Libyan Embassy 27 years ago. She was unarmed and only 25 years old. Ever since that day, I have been campaigning to bring her killer to justice and it is a case that remains extremely close to my heart.
Yvonne and I went to Gillingham School together in Dorset back in the early 1970s, before either of us went into the police service. I remember at the time of the killing, I was away on my honeymoon and it wasn't until I got back to England that I realised what had happened.
Like the rest of the nation and my serving colleagues, I was shocked, upset and understandably, angered. Although I knew the British Government couldn't do anything, watching the killers walk free from the country, back to the safety of Libya without any trial was heartbreaking and extremely frustrating. It left a bitter taste in the mouth of all police officers, not least Yvonne's family.
The hope of ever catching up with her killers was next to none all the while Gaddafi and his vile regime was in power. There was no reasoning with a man who actively promoted terrorism, a man who was responsible for the Lockerbie bombing and supplying arms and explosives believed to be used for murdering up to 100 Royal Ulster Constabulary Officers (now Police Service of Northern Ireland).
My anger was heightened even more so when the Prime Minister at the time, Tony Blair, agreed to 'call it quits' on a visit to the leader back in 2004. This was a real stab in the back to say the least.
However, the recent events in Libya and the fall of Gaddafi have given us the perfect opportunity to reopen the case and it has provided new hope of finally bringing Yvonne's killers to justice.
The Foreign Secretary William Hague has publicly recognised this opportunity and has begun talks with the transitional government. I am all too aware however, that Libya is in a vulnerable state of change and priority for the Libyan government, first and foremost, has to be the security and stability of its country and its own people.
There has been recent speculation that a couple of the murder suspects have been killed amongst rebel fighting, but it is hard to get absolute verification. Until we get the full picture of the truth, nothing is certain and we will continue to press for answers.
The right time will finally come to pursue the killers and bring them to justice and I, like many of my colleagues, will not rest until this day.
Criminals, terrorists and murderers have to know that no matter how long after the crime, the truth will catch up with them.