A former Police Federation chairman who "kissed and fondled" a woman whose complaint he had been handling has been found guilty of gross misconduct.
Sgt James Risby also messaged the woman asking her to send photographs of her underwear, a panel heard.
The Northamptonshire Police disciplinary hearing was told Sgt Risby had resigned on Friday.
Disciplinary panel chairwoman Jane Jones said he would have been dismissed if he had not already left the force.
She said Sgt Risby had been found to have sent "flirtatious, persistent and inappropriately personal" messages and to have engaged in "intimate and sexual" activity with the woman.
The panel heard that in 2018, Sgt Risby, known as Jim, had been assigned a complaint from the woman, who the hearing heard would remain anonymous.
Sgt Risby, who did not attend the hearing, later switched jobs to become an officer with the Police Federation, the professional body for rank and file police officers, but he continued to handle the complaint.
'Fondling and hugging'
The panel heard he sent 170 messages using WhatsApp on his personal mobile device "with the intent of starting a relationship with her".
Liz Briggs, representing the force, said Sgt Risby sent "repeated requests for photographs or descriptions of underwear that she was wearing or purchasing".
She added the pair had met at the Federation Lodge at the force's Wootton Hall headquarters on one of his days off and "both the officer and the woman confirmed that kissing took place".
"She calls it fondling and hugging," said Ms Briggs.
Sgt Risby was also accused of failing to report that the woman had told him she had been a victim of domestic abuse, but he had taken no action.
He had instead told her not to mention his name if she reported it, the panel heard.
Ms Jones concluded the evidence relating to the domestic charge "lacked detail" and was not proven.
In a statement to the hearing, Sgt Risby admitted exchanging messages with the woman on his mobile, but said he had not done so in order to avoid detection by force systems.
He also admitted to having had intimate contact with her and that she told him about issues relating to domestic abuse, but only in an historical context.