One penal development that initially met with Fry's approval was Millbank penitentiary. More than thirty years after the passing of the Act that first sanctioned their construction, the Holford committee concluded that ‘many offenders may be reclaimed by a system of Penitentiary imprisonment by which [we] mean a system of imprisonment not confined to the safe custody of the person but extending to the reformation and improvement of the mind and operating by seclusion, employment, and religious instruction’. The committee's report recommended to parliament the building of penitentiaries first in London and then throughout the country. Howard had advocated them and Bentham had agitated for his bespoke model to be built. Finally, what had eluded them, would be realised, although not according to either of their prescriptions.

Where the Tate gallery now stands at Millbank on the north bank of the Thames, once stood the General Penitentiary. It was the first panopticontype prison to be built, but was under state control, and not the private venture Bentham had envisaged. With one exception, Millbank marked the beginning of government incursion into penal administration. It was very much a national resource, a prestige project rather more befitting an imperial Britain than the other state resource, the dismal and decaying hulks. Unlike them it would be no transitory expedient but a permanent part of the penal estate and the flagship. It had no problem in constituting its superintending committee from the great and the good. Dukes, bishops and members of parliament were only too eager to be associated with this grand endeavour, none more so than George Holford himself. The country was convinced that, straddling the twin objectives of individual reform and general deterrence, Millbank was the answer to crime. Money was lavished upon it, money the increasingly rich country could afford. The nation deserved the very best in carceral innovation. The monetary outlay was more impressive than the ugly edifice it bought.