A woman assaulted by a Metropolitan police officer and wrongly arrested for bus fare evasion has said he treated her with “contempt” and that the attack had “devastated” her son, who witnessed the incident. The victim impact statement of Jocelyn Agyemang was read out in court as PC Perry Lathwood was ordered to pay a total of £2,950 following his conviction for assault last month. The police officer handcuffed and grabbed Agyemang by the arm, leaving it bruised, insulted her, and then detained her after wrongly suspecting her of fare evasion when she left a bus in Croydon, south London, in July last year. Lathwood was convicted of assault at Westminster magistrates court and on Friday was fined £1,500. He will also have to pay £200 compensation, costs of £650 and a victim surcharge of £600. The total of £2,950 must be paid within 56 days. Lathwood had been part of a team supporting an operation trying to catch fare dodgers. Agyemang left the bus with her seven-year-old son, whom she was going to leave at her mother’s house before going to an appointment in central London. A bus inspector asked her to show proof of payment, and she walked on and asked them to walk with her. She had paid via an Oyster card, which she held in her hand. Lathwood at one point called her a “daft cow” and when it was established she had paid, she was released from handcuffs and let go. Agyemang said in her statement to the court: “PC Lathwood manhandled me in circumstances where it was not warranted, but it was the look of contempt in his eyes as he did so that I find hard to move past. “His comment that I was a ‘daft cow’ was particularly degrading and I believe he intended it to be degrading. I have lost all confidence in the police service.” She said the incident had left her son “scared” and robbed him of trust in the police. The Guardian understands that the Independent Office for Police Conduct believes Lathwood, 50, from East Sussex, should face a gross misconduct hearing that could lead to him being sacked. One discipline charge relates to an allegation of sexism, for calling Agyemang a “daft cow”, and another to excessive force. Lathwood denies wrongdoing and will appeal against his conviction. Handing down the sentence, the deputy senior district judge Tan Ikram said Lathwood’s actions were a mistake, rather than an abuse of power. The judge, whose finding that Lathwood had assaulted Agyemang was criticised by some in policing, said: “On this occasion in my judgment the officer crossed the line and got it wrong. “It was not through bad faith. He faced a passenger who I have previously described as difficult and challenging but in my judgment he made a momentary error of judgment as it were in the heat of the moment.” The judge previously found that Lathwood’s claim that he acted to protect Agyemang’s child was “fanciful” and that the officer’s evidence “lacked all credibility”. Finding Lathwood guilty last month, the judge said: “There were not reasonable grounds to suggest arrest was necessary. The officer made an error of judgment and overreacted. I find you guilty of assault.” Lathwood claimed he was doing his job and after his conviction last month, the Met police assistant commissioner Matt Twist said the verdict was a “huge setback to our ability to rebuild trust with Londoners”. Twist also said that usually “when an officer is convicted of a criminal offence” they go before “an accelerated misconduct hearing as soon as possible”, but in this case “we do not intend to consider an accelerated misconduct hearing”.