Samantha Pariser is leaving her post as director of HMP Millsike, the UK’s newest prison, 11 months after it opened. Staff learned of the change on Friday 6 February.
Mitie, the private contractor that runs Millsike, said she would move to a new strategic role within the company. Millsike is Mitie’s first venture into running a UK prison. An interim director will take charge until a permanent appointment in June.
The prison, in East Yorkshire, received its first prisoners in March 2025. It now holds 850 men and will hold 1,400 once fully open.
Monitoring board concerns
In January 2026, Millsike’s Independent Monitoring Board (IMB) took the unusual step of writing directly to the Justice Secretary, David Lammy. The board raised concerns about security and conditions at the prison.
Its letter listed staff leaving doors and gates open, and men on constant watch managing to make ligatures. Roll checks sometimes took up to five hours. Regimes varied, and new arrivals could spend up to eight hours in reception.
The board linked some of the problems to an inexperienced workforce. Its letter gave one example: “Staff reported surprise when in early months they asked prisoners to help distribute canteen orders, only to later receive complaints that items are going missing.”
Company denies link
Mitie said the build-up of the prison was going to plan. It denied that Ms Pariser’s departure had anything to do with concerns about her performance or the running of the jail. A company spokesperson said the plan had always been for her to leave 12 months after the prison opened.
In a statement, the company said her role had been to lead Millsike through its first year, from mobilisation to full operation. It credited her with establishing a safe and stable environment that now holds nearly 1,000 men.
Paul Newton will serve as interim director. He has more than 35 years of experience in prisons. He has been governing governor of Drake Hall, Swaleside, Birmingham and, most recently, Hewell.
Sarah Mallender will take up the permanent director’s post in June. She currently leads the Mitie-managed Heathrow Immigration Removal Centre as its Centre Director.
Russell Trent, Managing Director of Mitie Care & Custody, praised the outgoing director. “Samantha has made an exceptional contribution during her tenure at HMP Millsike, helping guide the establishment from its construction phase into a safe, stable and fully functioning prison,” he said. He added that Mr Newton would provide continuity and momentum as the prison builds up to full capacity.
A 24-year career
Ms Pariser has worked in prisons for 24 years. In an article on the Mitie website last year, she wrote that she joined a large banking organisation after university. She later left to join a Prison Service graduate scheme, calling the move a leap of faith. She said she had wanted to do something more worthwhile.
In the same article, she rejected calls for a harsher prison environment. She argued that prisons should help people contribute to society after release and so avoid a return to custody. “Regardless of what many people would like to think, prison isn’t something that happens to other people,” she wrote.
