Ziyad Motala: In the first decision rendered by our Constitutional Court, Acting Justice Sydney Kentridge remarked that "if the language used by the lawgiver is ignored in favor of a general resort to 'values' the result is not interpretation but divination".

In a 5-4 decision in the Glenister case, the majority held that the disbanding of the Directorate of Special Operations (the Scorpions) and its replacement with the Directorate of Priority Crime Investigation, located within the South African Police Service, was unconstitutional.

The court was unanimous about the compelling need to fight corruption. It, however, split on the question of the relationship between the crime unit, the SAPS and the executive.

Constitutional interpretation sometimes involves subjects operating between grey and black latitudes, the contours of which pose profoundly complex political and legal questions. Difficult cases can arise from vague or unambiguous terms, or when the result is inconsistent with the purpose of the rule, or where different constitutional provisions have to be harmonised.

Glenister was not a such a case.

The majority opinion lacks cogency, depth of reasoning, or logic and fundamentally ignores the text and separation of powers. The majority's approach reflects a low water mark in South Africa's constitutional jurisprudence.

The court has to be mindful of separation of powers, particularly with respect to second guessing policy choices.

Section 179 of the Constitution provides for a single national prosecuting authority. Section 205 provides for the national police service, whose objects "are to prevent, combat and investigate crime, to maintain public order, to protect and secure the inhabitants of the Republic and their property, and to uphold and enforce the law".

As the dissenting opinion by Chief Justice Sandile Ngcobo noted, it falls within the power of parliament to establish an anti-corruption unit and to locate it within the SAPS.

The constitution does not mandate to parliament where to locate the anti-corruption unit. The executive has the prerogative to initiate legislation in this regard, and it is ultimately for parliament to make a policy choice.

The design, formulation and organisation of the anti-crime unit involves policy choices which are not the prerogative of the court.

The majority opinion, penned by Deputy Chief Justice Dikgang Moseneke and Justice Edwin Cameron, ignored the constitutional text which speaks about a single police service. They usurped the role of the co-equal branches of government and provided their preferred parameters.

The majority held that there is a constitutional obligation to create an independent anti-corruption entity. This obligation, they held, is both intrinsic to the constitution and also arises from various international instruments of which South Africa is a party.

In previous cases, the Constitutional Court has held that international law has relevance to the interpretation of the constitution, but is not self-executing until, and unless, it is incorporated into domestic law by legislative enactment.

In Glenister, the majority ignored all precedent and said international agreements, even though not made self-executing, create an obligation to create an independent anti-corruption entity. What makes the majority approach particularly egregious is there is no single international law text which supports their conclusion on the relationship between the anti-corruption unit and the executive. More importantly, there is not a single precedent from any country in the world which the majority could cite to support their interpretation that international law required an anti-corruption unit in terms of the framework they posited.

The majority approach undermines the very idea of the rule of law that is so central to constitutional jurisprudence.

As the dissent noted, judges should not, when faced with a text that is clear on the separation of powers, and policy choices, project their own preferences or values, nor create fringe meanings.

The court is unanimous in its concern about the scourge of corruption.

Under our constitution, the use of the investigation power and enforcement power cannot be selective. Selective investigation and enforcement constitutes tyranny and contravenes the constitution and legislative mandate of enforcement of the law without fear, favour or prejudice.

On the other hand, there is no support in the text of the constitution that gives court the authority to provide their parameters of how an anti-corruption unit should be constituted.

Under separation of powers, a court should not be making policy choices on the structure of the investigation authority.

If the legislature and executive create a structure, and it is found that the investigation and prosecution power is not properly exercised, a court has the power to review the decision for unconstitutional motives. This is what checks and balances entail.

The majority is unable to ground their claim of obedience on virtue. The authoritativeness proceeds from institutional power alone. We have an ethical claim of obedience not because of its intellectual correctness, but because the majority are part of an authority structure that is good to preserve.

Acceptance of the judicial interpretation because of the belief in the institutional virtue of judicial interpretation will not diminish cynicism, or the perception of the fundamental or egregious error.

Ultimately, it undermines the legitimacy of the court which is so important to democracy.

The majority also rest their conclusions on "public perceptions". A judge should not be looking at opinion polls nor, for that matter, the ballot box in saying what the constitution represents. If we looked at the passions of the majority, the death penalty would have been introduced a long time ago and gay rights would have gone out the window.

Mature democracies at times are confronted with decisions which are perceived as political judgments. Perhaps, the most infamous is the 5-4 US Supreme Court decision in Bush vs Gore, where five conservative justices went against every grain of precedent and the jurisprudence they previously espoused to award President George W Bush an election victory in the 2000 US elections.

Cherry-picking from international treaties and selectively invoking legal interpretations and simplistic suppositions (which cannot be supported by a citation of a single international tribunal or foreign court) might lead to the conclusion that the majority looked at this project through a strange lens.

In giving meaning to a constitution, judges follow disciplining rules which serve as overarching principles employed in the interpretation of the constitution. The judges are constrained by these principles and theories which seek to limit the value determinations they make in constitutional cases.

At the heart of the debate over constitutional theory is an attempt to ensure that judicial review is performed in a principled manner using reasoned standards, analysis and reasons that transcend the immediate result achieved in the case before the court.

What shaped the outcome in Glenister could lead some to conclude that this lens was ideological and political. The majority opinion showed a great distrust for democracy and disdain for political accountability.

Motala is professor of law at Howard Law School in the US and extraordinary professor of law at the University of Western Cape