Government's failure to provide a persuasive explanation for its decision to disband the Directorate of Special Operations (DSO), or Scorpions, has created understandable scepticism, the Institute for Democracy in SA (Idasa) said on Wednesday.

The institute, represented by researcher Gary Pienaar, made a presentation to parliament's justice and safety and security committees during public hearings into the draft legislation for the DSO's disbandment.

Rather than the public being obliged to fight a rear-guard action to save the Scorpions, government should be making its case in favour of the proposed new Directorate of Priority Crime Investigation (DPCI)provided for in the draft legislation.

Government should be explaining to the public why it believed the DPCI would make a more effective contribution than the Scorpions had to date, Pienaar said.

"Government input has been largely limited, on the other hand, to repeated insistence that it will be more effective rather than elaborating on that assertion."

Government's presentation on the review of the criminal justice system (CJS) to the committees on Tuesday had failed to mention the Scorpions at all in its frank and detailed analyses of the problems characterising the CJS.

"Far less did it disclose a convincing rationale for the creation of a new unit to replace the Scorpions," he said.

On the contrary, the review had made it quite clear that if approved, its effects would be extensive disruption to, and engineering of, the CJS, including the SA Police Service.

This was about the fourth review of the CJS in the past ten years and there was no guarantee that this one would produce even better results.

Pienaar said it made no sense to dissolve the relatively effective Scorpions and then to create a "less able and more junior unit", and to replace the Scorpions in circumstances of such extensive turmoil that were envisaged.

At best, at the very time when any new unit required focused and devoted attention, it would have to compete with numerous alternative imperatives for the National Police Commissioner's time.

This practical consideration of time alone, raised fundamental questions regarding the attainability of the proposed objectives of the legislation.

The draft bills were also based on an incorrect premise and incorrect interpretation of a section of the Constitution.

"Any claim that this section's reference to a single police service requires the disbandment of the DSO is incorrect in law, as I'm sure is commonly acknowledged by now," he said.

This interpretation entirely ignored other provisions specifically allowing for the possibility of additional law enforcement structures.

The two bills were further in clear contradiction of the Khampepe Commission's central conclusions and recommendations about the Scorpions.

Pienaar said public submissions on the issue were within their rights to include requests for the retention of the Scorpions, albeit with adjustments or improvements to the model and legislation.

"Regardless of any government or parliamentary majority, any differing views should be considered on their merits and not reduced to a simplistic numbers game.

"We believe that the public interests in improving the prospects of the fight against complex commercial and organised crime should take account of public interest rather than public numbers," Pienaar said.