Kāpiti Coast councillor David Scott has been found guilty of indecent assault.
The jury in the trial at Wellington District Court took three and a half hours to reach the verdict.
David Scott, 71, had earlier pleaded not guilty to one charge of indecent assault.
Scott said outside court that his family would be devastated by the verdict.
"I haven't had any sleep for a year and two months."
He said he was not sure how the verdict would impact his role as a councillor. He said he hoped to be at Kāpiti Coast District Council tomorrow.
The Crown has argued Scott pressed himself against a Kāpiti Coast District Council employee at a morning tea following a council meeting in April last year.
In her closing address to the jury lawyer Kate Feltham said the complainant was a professional woman who took her job seriously.
"The evidence she gave was given in a calm, coherent, logical way. She was sure of what happened."
Feltham pointed out the complainant was not sure about the measurement of the male genitalia she said she felt pressing into her but under cross examination she was asked again and only guessed it was about four or five inches.
Feltham told the jury the measurement of the defendant's penis in relation to his wallet was irrelevant.
"She was guessing about the length of something she was feeling through her clothing and through David Scott's clothing as opposed to the very precise measure that he had by the doctor yesterday. We also of course, to state the obvious, don't know the exact state of the defendant's penis and if it was exactly the same on both occasions."
Feltham said it could not have been Scott's wallet the employee felt because he kept his wallet in his right pocket not the left, which is the area the complainant said she felt the penis.
"Now whether she felt his penis or whether she felt something else, I suggest doesn't actually matter because his actions in grabbing her, holding her and thrusting himself into her were what made it indecent."
Feltham said when the complainant turned to look around there was plenty of space.
"So clearly it was a deliberate act on his part to come so close and to grab her in that way."
In his closing address to the jury defence lawyer Mike Antunovic said the measurements were relevant.
Under cross examination he asked a Crown witness to measure Scott's wallet which was about four and a half inches.
"Isn't that a coincidence, members of the jury, that the wallet actually is as long as the dimensions of this penis that she said she could feel", Antunovic said.
He said the 5m by 3m morning tea room was full with people, especially during the first part of the break when the incident was alleged to have happened.
Antunovic said 26 people were invited to the morning tea.
"Is there any room for people to press into each other, to bump into each other, to squeeze past each other in a situation like that? Of course the answer has to be yes."
Antunovic also questioned what sense it made to choose that moment to commit the alleged offence when the complainant was talking to the mayor in a room with other people.
"To do something like that deliberately in those circumstances is just nuts, crazy and utter nonsense."
Antunovic said the alleged thrusting was at the heart of the case because that was what made it indecent.
But he said the Crown had not proved that beyond reasonable doubt and the complainant had exaggerated her account.
Antunovic asked that a conviction not be entered and Judge Peter Hobbs agreed not to.
Scott has been remanded on bail until June 19 for sentencing.
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