The older brother of murdered toddler Cheryl Grimmer has been cleared of rape charges after a judge accepted medical evidence showing he was sexually impotent at the time of the alleged offences.
Stephen Vincent Grimmer sat through a six-day trial in Wollongong District Court that ended on Wednesday when Judge Justin Smith found him not guilty of three counts of sexual assault.
Judge Smith found Grimmer's accuser, an adult female known to him, was an unreliable witness and said her "implausible" story, together with the medical evidence that showed Grimmer was suffering from erectile dysfunction at the time, was enough to cast doubt on the veracity of the allegations.
Grimmer appeared in court via video link from jail, where he is currently serving a sentence for separate, unrelated child molestation charges stemming from an incident in April 2016 where he inappropriately touched a 14-year-old girl while holidaying at Sussex Inlet.
Judge Smith labelled the woman's evidence "implausible", saying it was both internally inconsistent and inconsistent with other evidence he accepted.
"I don't accept that the complainant's evidence is reliable," he said in acquitting Grimmer of all the charges.
The court heard the woman claimed Grimmer raped her and tried to put his erect penis in her mouth sometime between 2016 and 2018, then threatened to punch her if she told anyone.
However, Grimmer's ex-partner gave evidence in the trial, corroborating medical evidence that Grimmer was suffering from erectile dysfunction at the time and was unable to "obtain or maintain" an erection.
Judge Smith accepted the evidence, and noted that Grimmer had denied the allegations during an interview with police and maintained his innocence throughout the trial.
He acknowledged that Grimmer's attitude towards the woman and her mother during his interview with police had been negative, but found it was not necessarily an indication of a guilty conscious.
"His demeanor and what he said about the complainant was equally consistent with a person being faced with very serious but baseless allegations," he said.
Grimmer will become eligible for parole on the child molestation charges in March next year.
Grimmer, along with his brothers Paul and Ricki, have spent decades trying to unearth what happened to their three-year-old sister Cheryl, who disappeared from Fairy Meadow Beach in January 1970.
Police suspect Cheryl was kidnapped and murdered but the case remains unsolved to this day.
There is no suggestion Grimmer was responsible for his sister's disappearance - he was only six years old at the time.
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