In 2026, the Offender Database recorded that former Sergeant Mark Pattison—formerly of Hertfordshire Police and Thames Valley Police—was placed on the barred list following a gross misconduct hearing. The investigation established that Pattison, while a supervisor at Hatfield Police Station, engaged in an affair with a “significantly junior” detention officer, known as Ms A. The prosecution reported that their sexual activity occurred between December 2021 and February 2022, including a “naughty” tryst on a station stairwell during a night shift.
The investigation established that Pattison abused the clear power imbalance within his team, as Ms A had only recently completed her probation when the affair began. The prosecution reported that although Pattison admitted to the relationship, he “categorically denied” engaging in sexual activity at the station. However, the misconduct panel ruled that his desire for “sexual gratification” while on duty superseded his professional obligations, concluding that he would have been sacked had he not already resigned.
Judicial Findings and Barred List Status
The court reported that the behavior of both Pattison and Ms A brought significant discredit to the police service. The investigation established that the pair were absent from the custody suite for approximately 12 minutes to engage in the stairwell encounter. The prosecution reported that during the hearing led by Thames Valley Police, the panel determined that Pattison’s conduct amounted to gross misconduct and a total failure to uphold the high ethical standards required of a supervising officer.
Judge-led proceedings at the misconduct panel concluded with Pattison being officially barred from policing for life. For his actions at Hatfield Police Station and the nature of the “disgraceful” breach of trust reported, he can never again serve in any UK police force or law enforcement capacity. The panel noted that his actions were not merely a private matter but a professional violation that undermined the integrity of the Hertfordshire and Thames Valley forces.
Status and Statutory Requirements
Based on the misconduct ruling issued on 14 April 2026:
- Professional Status: BARRED FOR LIFE (Placed on the College of Policing Barred List).
- Legal Status: DISMISSED (Would have been sacked if he had not resigned).
- Supervision Status: N/A (Internal police misconduct finding; no criminal conviction for sexual offences recorded).
- DBS Status: Likely flagged (Misconduct involving an abuse of power/position is recorded and disclosed on enhanced checks).
- Judicial Oversight: Conducted by a Thames Valley Police misconduct panel; investigated by Hertfordshire Police.
- Criminal Record: No criminal charges; Gross Misconduct proven for “Abuse of Position” and “Sexual Activity on Duty”.
- Origin: Hatfield Police Station, Hertfordshire (Formerly of Thames Valley Police).
Monitoring and Public Protection
Pattison is managed under the statutory requirements of the College of Policing Barred List. Due to the nature of his conduct—specifically his “predatory” abuse of a junior colleague and his decision to prioritize sexual activity over his duties in a custody suite—he is a priority for exclusion from all future public office roles. Authorities reported that the 2026 ruling ensures Pattison is legally prohibited from any role involving the exercise of police powers or the supervision of law enforcement staff.
As a barred former officer, his details are permanently logged on the national police database of dismissed staff. Authorities state that Pattison’s history identifies an individual who prioritised his own “naughty” gratification over the human rights and professional safety of his subordinates. Any attempt by Pattison to re-enter the policing sector in Hertfordshire or elsewhere will result in an immediate block to ensure the ongoing integrity of the public service from a man who has violated the principles of professional decency.
QUESTION – Given that the sergeant was “Absent for 12 Minutes” from a high-stakes environment like a custody suite, do you believe that “On-Duty Sexual Activity” should be legally reclassified as a criminal offence of “Misconduct in a Public Office” rather than just a disciplinary matter?
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