PC Simon Read claimed at a disciplinary hearing that he made an honest mistake at the self-service tills at Tesco Extra in Wisbech, Cambridgeshire but a panel ruled that his explanation was “lacking in credibility”.
He scanned the carrots barcode twice and failed to scan the donuts barcode, paying around £4 for the items instead of about £14.
A manager at Tesco later alerted police to reports of a “suspicious police officer at its store” and the matter was investigated, Thursday’s hearing in Peterborough was told.
Sharmistha Michaels, the legally-qualified chair of the disciplinary panel, said: “On the balance of probabilities we are satisfied that Pc Read did intentionally scan the wrong barcode.”
Pc Read claimed he had not checked the screen of the self-service till, but CCTV showed him looking at it to select his method of payment, Ms Michaels said.
Lawyer Mark Ley-Morgan, who set out the misconduct case, said it was “an officer effectively stealing while in uniform”.
“He was using his uniform as cover,” said Mr Ley-Morgan.
“Who would be suspicious of a police officer?”
Carolina Bracken, Pc Read’s lawyer, said he had an “unblemished career” before the incident and was involved in Donald Trump’s visit to Blenheim Palace and several royal weddings while serving with Thames Valley Police from 2008.
He had previously served in the armed forces and joined Cambridgeshire Police in January of this year.
Ms Bracken said that the case weighed heavily on Pc Read and he had received prank calls in the night from people offering him doughnuts.
Pc Read has a right to appeal against the decision. He had earlier told the panel he was buying the sweet treats for colleagues as a “cake fine”.
“Cake fines are fairly common in the police,” he said.
“It’s a way of being punished in a light-hearted way.”
He said people could be given a “cake fine” if they were having a bad day, or if they were joining or leaving a department.
Pc Read said he was buying the carrots for his sergeant who was on a diet, and he thought it “would be funny” for them to be in a Krispy Kreme paper bag.
Reporting by PA