Sean Hackett, the former captain of Tyrone's minor footballers, is accused of murdering his father Aloysius in January 2013.The teenager admits shooting his father dead, but he denies murder on the grounds of diminished responsibility.Mr Harte told the jury that Sean Hackett was "a nice young man" and one of the best Gaelic footballers of his age group."I had my eye on him as a future Tyrone player," he said. "He had a lot to look forward to as a very talented Gaelic footballer."A few days after Aloysius Hackett was killed Sean Hackett was granted temporary release from prison to attend the funeral.He was chaperoned at the funeral by his solicitor and by Mickey Harte. Since then Mr Harte has visited the accused three times in prison.Mr Harte told the murder trial that on the sports field Sean Hackett displayed leadership qualities and was a player that others looked up to.Earlier the court was told Sean Hackett knew that killing his father was an abhorrent and immoral act but he believed it would provide "the ultimate solution" to his depressed mental state.Aloysius Hackett, his 60-year-old father of four, was targeted as he arrived at the family home near Augher. He was shot twice in the head and died at the scene.Sean Hackett's lawyers claim he was suffering from depression at the time of the shooting and believed killing one of his parents would place them in heaven to watch over him.The prosecution, however, told the jury that psychiatrists who examined the accused in prison found no signs of depression.Prosecutors suggested that Sean Hackett was capable of acting logically and rationally.They say he planned the shooting carefully, choosing the weapon and practising with it, then choosing a moment when no witnesses were present to shoot his father in the head before taking time to hide the rifle.Consultant psychologist Dr Philip Pollock, who interviewed Sean Hackett on behalf of the defence, told the court the accused suffered mild depression around the time of the killing.Dr Pollock told the jury that Sean Hackett believed putting a parent in heaven would provide a distraction and relief from his unhappy life.However, the psychologist indicated that the defendant knew that killing was wrong."He knew what he was doing in this respect," said Dr Pollock, "that what he was doing was an illegal and immoral act ... out of the killing he would provide himself with the ultimate distraction, the ultimate solution."The trial continues.