The Gulf Centre for Human Rights (GCHR) is launching a judicial review of the tender, alleging that the department has no legal power to carry out the activity.
The existence of the MoJ’s commercial body, Just Solutions International (JSI), was revealed earlier this year but little is known about its purpose or operations.
Lawyers for GCHR allege that competing for profit-making contracts for consultancy services overseas is not a “governmental purpose”.
Other than raising revenue for the MoJ, the organisation argues, JSI’s aims are not of public benefit and therefore it is “ultra vires”, or beyond the powers, of ministers to operate such a scheme.
The MoJ has so far declined to release detailed information about the deal. Saudi Arabia has been widely criticised for its human rights record. There has been an international outcry over the case of Raif Badawi, who was sentenced to 10 years imprisonment and 1,000 lashes for advocating freedom of expression online.
Melanie Gingell of GCHR stated: “By providing services to the Saudi prison and probation service the UK is lending legitimacy and indirectly supporting such abuses.
Adam Hundt, of the law firm Deighton Pierce Glynn Solicitors which is acting for GCHR, said: “It is surprising that JSI’s activities have taken place shrouded in secrecy, and without parliamentary debate or approval.
Because of restrictions to judicial review, GCHR is seeking to crowdfund its legal challenge.
According to MoJ reports, JSI has recently won a contract to provide services to Macedonia and has put in a bid to advise on new prison in Oman.