There are times when Parliament sparkles with the political activism that in bygone years was the lifeblood of many of the MPs who occupied its benches.

Some would say the examples are becoming increasingly rare as the African National Congress (ANC) exercises a centralised grip over its cadres and party organs. They might suggest the institution is a fading star rather than a beacon of light, and they could point to its ignominious collapse under the weight of executive interference in the handling of the arms deal investigation, amongst other things.

And there is indeed validity in the view that on issues such as the soundness of government's political decision-making or the vulnerabilities of the party and its members to public exposure and attack, there is a closing of ranks that undermines the institution's integrity. Critically important areas of contested government policy stay out of bounds for political debate, constraining the effectiveness of Parliament as an oversight body.

It is a constant battle for party members with alternative views to open up discussion on these topics.

The workings of the parliamentary ethics committee is further evidence of how the party closes ranks to protect its own. One example is the tardiness with which action was taken against Winnie Madikizela-Mandela.

The committee decided that action a public reprimand and fine should be taken against MadikizelaMandela only once the fact of her failure to disclose the receipt of gifts and donations in Parliament's register of members' interests was an incontrovertible fact of court record.

The committee, after delays of more than a year, also failed to wrap then minerals and energy minister Penuell Maduna over the knuckles for disparaging remarks on the integrity of the auditor-general, whose position is constitutionally protected.

It is within this context that the committee's approach to dealing with former ANC chief whip Tony Yengeni, who has confessed to defrauding Parliament by not disclosing his receipt of a 47% discount on a luxury 4x4 Mercedes-Benz, will be watched closely. If past experience is anything to go by, one can expect that ways will be sought to preserve his position as far as possible.

Another of the blind spots that is off bounds for parliamentary committees is government's HIV/AIDS policies. It is quite astounding that Parliament, as one of the central oversight bodies in society, has failed to devote special attention and time in public hearings to an epidemic expected to claim more than 300 000 lives this year alone.

Dissatisfaction with suppression of debate on the topic was rumoured to be behind the departure of Pregs Govender, head of the committee on the status of women and children.

The crippling of the effectiveness of the public accounts committee during the arms deal probe left it largely denuded of any ability or confidence to bring government departments effectively to account. Once a feared and powerful body, the committee, which plays a critical oversight and probing role in other democratic governments, has disappeared into the background. The debacle of the arms deal probe saw Andrew Feinstein, another ANC stalwart, depart.

The party's hold over the caucus and its dislike of divergent views has become a source of dismay to several MPs, who have opted to leave rather than to submit to it.

Executive interference has also been apparent during the processing of legislation by committees. ANC committee chairmen are not allowed to stray too far from executive wishes in amending proposed laws.

However, despite these constraints and outside the parameters of the ANC's political self-preservation, there have been remarkable instances of forthright independence and decisive social intervention. Sometimes this is evident in committee amendments to proposed legislation, changes often aimed at promoting consumer protection and introduced after listening to interested parties.

The finance committee under Barbara Hogan has been unbending in fulfilling its social mandate. It recently refused to pass an amendment that would have freed the life insurance industry from the constraints of the in duplum rule on loans taken out by policyholders.

In other cases, this parliamentary oversight relates to matters of a more general social concern. So for instance communications committee chairman Nat Kekana has been focusing the spotlight on transformation in the advertising industry and overcharging by cellphone companies.

Sometimes when the legislative load is excessive, parliamentary committees have little time to play the oversight role as they would like to. When they do, the results can be stunning in promoting awareness and acting as a catalyst for social change.

With acknowledgements to Linda Ensor and Business Day.