About 3,200 gang members, 8,400 people convicted of domestic violence and 15,900 robbery cases are also among the “medium risk” offenders set for private supervision, the National Association of Probation Officers said.
The public will be put at risk if such offenders are taken out of the care of the public sector and transferred to private firms such as G4S and Serco, the union said.
Speaking yesterday, its general secretary Harry Fletcher said: “The Government’s plans are both chaotic and dangerous.”
More than 50 cases have been examined by the union as examples of “complicated” medium risk offenders.
Among the offenders who would be transferred to the private sector under Justice Secretary Chris Grayling’s shake-up of rehabilitation, are a 32-year-old repeat offender in Greater Manchester who was convicted for violence against a child.
Mr Fletcher went on: “Splitting up offenders between the public and private sector according to risk threatens public protection.
“Offenders are generally not a compliant, problem free, group of people. They disproportionately suffer from mental illness, are four times more likely than the general population to misuse drugs and are 10 times more likely to have been in care.
“They need to be supervised by experienced staff who can motivate them and properly assess risk.”
He added: “The Government plan to outsource the supervision of medium and low risk offenders is a disaster waiting to happen.”
The union said the Probation Service has met or exceeded all its targets in the last year and reoffending rates for those on community orders fell by 5.6 per cent.