This week, Home Office and Ministry of Defence civil servants will meet to discuss whether they can make Mr Howard's idea, which has been approved by the Defence Secretary, Michael Portillo, work.
They will be told it is legally impossible for civilians to be treated like the court-martialled soldiers imprisoned in the country's only existing "glasshouse" - the military corrective training centre at Colchester.
"This idea is designed to please the Conservative party conference," said one senior Home Office official. "It came from the minister's political office. You can imagine what roars of approval there would be if he announced, `I'm going to send young thugs to the glasshouse'."
But many civil servants agree that Mr Howard cannot impose military law on civilians. If young offenders go to Colchester, which currently has about 100 of its 210 places empty, then a wing of the prison would have to be declared a civilian jail.
"This will mean that inmates will have access to the prisons ombudsman, boards of visitors and Judge Stephen Tumim's prisons inspectors, and would be able to cite the Prison Service rules when their rights were infringed," said Stephen Shaw, director of the Prison Reform Trust. "In other words, prisoners can go to Colchester, but all the wet liberal safeguards the Conservative faithful appear to dislike so much will be in place.
"I suspect Mr Howard was not planning to mention this at the conference."
John Wadham, legal officer for Liberty, said the 1952 Prisons Act and 1994 Criminal Justice Act were clear on the process for designating civilian jails. If Mr Howard was in any doubt, he said, Liberty would happily take up the first case of a civilian put under military law and sue the Home Office for unlawful imprisonment.
If ministers do designate part of Colchester as a jail, it is unclear that they can force civilians to undergo the punishing exercise regimes that soldiers endure. A Prison Service spokesman said yesterday that none of the details had been worked out.
The proposal is also meeting opposition in the MoD. Malcolm Rifkind, the previous defence secretary, rejected the initial overtures from Mr Howard. It was not until Mr Portillo took over earlier this year that the glasshouse plan was reborn.
Many senior officers do not see why the forces should deal with juvenile delinquents. They say that although the Colchester jail is half-empty now, the number of convicted servicemen usually rises rapidly in military emergencies and the cells could well be needed in future.
More disturbing for Mr Howard and Mr Portillo than the opposition of civil servants is the evidence that Colchester is not as tough a jail as they appear to believe. Its commandant, Lt-Col Patrick Gascoigne, sounded more like a probation officer than a drill sergeant last year when he described his charges as products of "broken homes and lack of parental guidance".
Most of the prisoners are not being held for crimes but forbreaches of military discipline and will return to their regiments when they have served their sentence. About a third of the men and women are in Colchester's cells for being absent without leave, a quarter for dishonesty and a sixth for insubordination.
The jail's aim was to "retrain prisoners for entry into the forces", said the commandant. Among these servicemen's and women's routines are weapons drills, which Mr Howard is not expected to extend to young offenders. The remainder leave the Army at the end of their sentence and are taught to ``develop self-sufficiency and the will to become responsible citizens".
The atmosphere of paternalism is reinforced by the prison buildings. The original Nissen huts were built in 1942 for prisoners of war. They have been demolished (except one which is open as a museum) and in their place are low red-brick buildings around a parade ground. There are dormitories, lavishly equipped workshops, a cottage hospital, interdenominational church and working farm.
Colchester is distinguished from civilian jails not only by the fact that many of its inmates have committed no crime the rest of society recognises, but by its obsession with cleanliness and physical training. Former inmates said the exercise routines were very hard to take.
One MoD employee said in an anonymous letter last year that "the enduring memory most have" of the first three weeks of intensive exercise and drill is "always being hungry". The food was poor and the portions small, he said. The atmosphere of the jail was oppressive; officers read all inmates' mail, and discipline "was administered in semi-secret, with fear as the motivator". But Stephen Shaw from the ultra-liberal Prison Reform Trust, which never misses an opportunity to point out faults in the Prison Service, toured the jail last year and was pleasantly surprised: "Compared with most civilian prisons, it's quite a nice place."Reuse content