A murder-suicide involving the Swiss Guard that rocked the Vatican in a mystery worthy of a Dan Brown thriller is back in the spotlight after Pope Benedict XVI was asked to intervene and reopen the case.
Swiss Guard Cedric Tornay, 23, shot dead the famous unit's commanding officer Alois Estermann, 43, and his wife Gladys Meza before turning the gun on himself - allegedly in a fit of rage after being overlooked for promotion.
Within hours of the triple deaths in 1998 - the first violent deaths on Vatican soil in decades - officials closed the case saying it was a simple case of corporal Tornay having gone mad after being given medication for a brain tumour.
Acting under the influence of the drugs he wreaked a terrible revenge using his own firearm, with the shots being heard by then Pope John Paul II, after he was refused promotion.
However theories of a cover up have long been rumoured - this is the Vatican after all and they have a history of covers ups - and Tornay's mother Mugette Baudat has constantly accused the Catholic Church hierarchy of concealing evidence.
Questions were raised as to how the Vatican investigation came to such a speedy conclusion before the day was out but they have always refused to reveal any further details and now Mrs Baudat has written to the Pope asking him to 'open the files on the case and remove any doubts.'
It is not the first time that she has asked the Vatican to reopen the case and each time they have not responded to her request but this time she has gone a step further and appealed directly to Pope Benedict and asked for his intervention.
Lawyer Luc Brossellet, who is representing Mrs Baudat, said:''Times have changed and the Vatican and Pope Benedict has said that the Vatican must follow international law. That's the reason we have written this open letter to Pope Benedict in the hope that he will look again at this case.
'Errors were made in the initial investigation and we have asked before for the case to be reopened but we never received any response from the Vatican. Hopefully this time we will.
Following on from all the publicity surrounding pedophilia in the Catholic Church the Vatican has said it will be more open so we are hoping that this spirit of openness will stretch to this case.'
Mr Brossellett added that he had found 'inconsistencies' in the official autopsy report provided by the Vatican after they had a second one carried out in Lausanne when the body was returned to his native Switzerland.
He said:'Our autopsy showed that Cedric Tornay was turned at the time of the shot but the Vatican one said he was on his knees and facing forward. So their reconstruction is wrong.'
Mr Brossellett also said that they had discovered the night of the murders a friend of Estermann's had called his apartment and had heard 'bangs and shouting' and that he thought four people were in the house at the time of the killings.
Mrs Baudat said: 'As far as I am concerned the original investigation is full of lies and contradictions and was carried out at such a speed so as to hide the real truth. It was a murder carried out to get Estermann out of the way and then helpfully blame it on a dead madman.'
In the weeks after the shootings in May 1998 there were reports that Estermann was an East German spy who Tornay had uncovered while there were also suggestions that both were homosexual and having an affair - the scandal of which would have been too much for the Vatican.
The Swiss Guard, which celebrated its 500th anniversary in 2006, is noted for its yellow and blue striped Renaissance uniform and were started as a mercenary army to protect the Pope.
Three years ago current commander Daniel Anrig was forced to deny accusations of brutality during his time as a policeman in Switzerland before moving to his current job at the Vatican.