A police force was told an officer had "repeatedly asked a 15-year-old girl to send naked pictures of herself" before he went on to commit a child sexual offence, a new inspection has found.
The incident was flagged as one of at least five opportunities lost by Thames Valley Police to take stricter action against former PC Luke Horner before he engaged in penetrative sexual activity with a child aged 13 on 11 June this year.
The Police and Crime Commissioner for Thames Valley commissioned His Majesty's Inspectorate of Constabulary and Fire & Rescue Services (HMICFRS) to consider if there had been any lost opportunities in how the force dealt with intelligence and information relating to Horner during his service.
HMICFRS concluded Thames Valley Police could not have reasonably anticipated Horner would commit sexual offences against a child.
But the inspectorate found the force lost at least five opportunities to take stricter action against him, both at the initial vetting stage and during his police service, which could have led to him being refused initial vetting clearance or being dismissed.
Horner, who resigned as an officer on 26 July, travelled to Rushden in Northamptonshire while off duty to commit the offence, which he also recorded on his victim's phone, the court heard.
He was jailed earlier this month for six years and four months.
The force should have made further inquiries at the initial vetting stage into two separate issues - a potential sexual assault allegation in 2016 and his early departure from the British Army, HMICFRS found.
During his police service the force failed to identify that there were questions about his honesty and integrity after several incidents - and when considered together, these incidents "clearly indicated that Horner was not suited to being a police officer".
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Anonymous Crimestoppers tip
During Horner's police service, the force's counter-corruption unit received anonymous intelligence from Crimestoppers which suggested he had been chatting online to a 15-year-old girl and had "repeatedly" asked her to send him naked pictures of herself.
The counter-corruption unit made one attempt to contact the person who gave the information to Crimestoppers, but the inspectorate said the unit should have made "repeated and exhaustive attempts" to contact them within the 14-day period the communication channel remained open.
Supervisors also identified that Horner "did not always handle evidence correctly" - in one incident officers found some cannabis in Horner's work tray and in another, he took various items of evidence home in his bag, which he later reported stolen.
In another incident, he pointed his taser at a colleague and activated the red dot laser - at the time he was the subject of a live written warning for the mishandling of evidence, so the inspectorate believes the professional standards department should have "without hesitation" assessed the behaviour as gross misconduct, which could have led to a gross misconduct hearing, with a potential outcome of dismissal.