The 81-year-old ex-military officer, alleged to have sexually assaulted his 17-year-old granddaughter, was on Friday acquitted and discharged by the Accra Gender-based Violence Court, following the prosecution's failure to make a prima facie case against him.Stephen Atia's acquittal followed a medical report from the Police Hospital that he is impotent, because his penis could not erect, upon a series of medical examinations.However, the test could not indicate the period over which Atia has been impotent. The court, presided over by Justice Georgina Mensah-Datsa, held upon the closure of the prosecution's case, Friday, that it was difficult to determine that Atia, who was charged with incest, had indeed had sex with the victim (name withheld).“The victim testified under cross-examination that she could not tell whether or not the accused had sex with her, since she only woke up to find her grandfather on top of her,” the judge held, adding that her decision was further reinforced by the evidence of the medical officer who conducted the potency test on Atia.“In the circumstances, it is difficult to hold that the accused had sex with the victim,” Justice Mensah-Datsa said, adding “I have no option than to hold that the prosecution has not made a prima facie case for which he must be called upon to open his defence.” Atia was accordingly acquitted and discharged.It was the prosecution's case that about two years ago, the victim's mother died and the father who is an umbrella repairer could not cater for her.According to Assistant Superintendent of Police (ASP) Sarah Ekua Acquah, the father, thus, took the victim and her two other siblings to live with the accused person.The accused is said to have during the period sexually assaulted the victim four times. The prosecution said although the victim warned the accused person, he continued to have sex with her.The prosecution told the court that the victim, who could not bear her ordeal, reported the incident to her head-teacher who also reported it to Orphan Aid Africa Orphanage which withdrew the victim and her siblings from the accused person's home.A report was subsequently made to the police. He was then arrested on October 8, 2011 and after investigation he was put before the court on October 10, 2011.