Staff misconduct admitted at HMP Chelmsford raises oversight concerns
A teacher who provided tuition at HMP Chelmsford has admitted misconduct in a public office after she sent sexually explicit images of herself to an inmate and supplied prohibited digital files.
The defendant, Oksana Antanaitiene, 51, of Bradleigh Avenue, Grays, pleaded guilty at Chelmsford Crown Court on Tuesday and was granted bail. A sentencing hearing has been listed for 28 October.
- Police inquiries began after staff discovered the tutor locked in a room with a prisoner in August 2025.
- Officers later found a USB device and explicit images during a search of the inmate's cell.
- Prosecutors say Antanaitiene also transferred music and television files to the prisoner via the USB drive and maintained contact by letter and phone.
Essex Police said searches of a vehicle and an address connected to Antanaitiene uncovered "other items of significance". The Crown Court was told the tutor admitted the inappropriate relationship to prison managers the day after the initial incident.
"She chose to enter into an inappropriate relationship with a serving prisoner and continued that relationship through repeated contact and the sharing of prohibited items and explicit material,"
said DC Matthew Parker of the force's prison investigations team. He added that her actions had the potential to undermine prison safety and the institution's integrity.
The case is the latest to attract attention at the Chelmsford establishment on Springfield Road, which has seen a number of staff-related controversies in recent years. The facts presented so far focus on alleged breaches of professional boundaries by an individual employed to deliver education inside the prison.
What the court heard and next steps
Court records and police statements set out a sequence of events beginning with the discovery of the tutor locked in a room with a serving prisoner in August 2025. A cell search the following October reportedly located explicit images and a USB stick concealed in a dressing gown. Antanaitiene was charged with misconduct in a public office in July and admitted the offence at her hearing in September.
| Key date | Event |
|---|---|
| August 2025 | Found locked in a room with a prisoner at HMP Chelmsford |
| October 2025 | Search of inmate's cell finds USB and explicit images |
| July 2026 | Charged with misconduct in a public office |
| 22 September 2026 | Pleaded guilty at Chelmsford Crown Court |
| 28 October 2026 | Sentencing scheduled |
Essex Police emphasised that Antanaitiene had received training on corruption prevention and the delivery of teaching in a custodial environment. The force said officers from its prison investigations team conducted the inquiry.
Beyond the immediate criminal proceedings, the case will be of interest to the prison service and local community because it touches on how external staff are supervised and the safeguards in place to prevent the introduction of unauthorised material into secure settings. The presence of digital media and the purposeful transfer of files to a prisoner are matters that prison authorities regard as serious risks to both security and inmate management.
When staff entrusted with education and rehabilitation fail to keep professional boundaries, it can compound concerns about institutional culture and oversight. The court will hear submissions on sentence next month, and any outcome may influence internal reviews at HMP Chelmsford or policy discussions about training and monitoring of external contractors and tutors.
Police invited anyone with relevant information to come forward as inquiries continue. The prosecution and defence were in attendance at the latest hearing, and the defendant remains on bail pending sentencing.
