According to testimony and the forensic evidence, prosecutors state that the man attempted to seduce the woman while at a tennis club party.
After she rejected his advances and left the party, he followed her into the garden, knocked her out with a blow to the head, and raped her while she remained unconscious.
He then left her bleeding on the ground in the rear garden of the club, where her body was discovered 40 hours later, when her friends went searching for her.
The woman had been mourning the death of her husband.
In his defence, the man claimed that the pair had had consensual sex in the garden, and that she had accidentally fallen and hit her head. He further claimed that she was fine when he left the scene.
Part of the complex nature of the trial was related to the interpretation of the forensic evidence, which suggested the woman had died as the result of injuries sustained from a fall - likely triggered by an initial blow from the man.
The prosecution held that a charge of murder was not the only option, and that her death was not only a result of his action, but also a result of inaction. "He failed to allow the victim to get medical help," prosecutor Christian Hubmer said.
"According to the experts, her chances of survival would have been significantly increased if first aid had been given immediately."