"This could be the biggest crisis of all for Thabo Mbeki's government, bigger even than AIDS ." 

"The way this turns out will determine whether we go the Nigerian route ." "This is a litmus test for the African National Congress (ANC) ." Given that these are among the views emanating from inside the ANC on the importance of the probe into possible corruption related to the R43bn arms package, no one should doubt the importance of the process that lies ahead.

The investigation was set up after the auditor-general found "material deviations from generally accepted procurement practices". He also found evidence of large price escalations and indications that the offset arrangements were less favourable than previously claimed.

After considering the report, Parliament's standing committee on public accounts last month initiated a multipronged investigation involving the auditor-general, the public protector, the Office for Serious Economic Offences, the national prosecuting authority and the Heath special investigating unit.

Why a potential crisis? There are suspicions the investigation could lead close to the pinnacle of government and could touch some highly revered former members of Umkhonto we Sizwe, the ANC's former armed wing. Why the talk of the Nigerian route? Because if talk of cronyism, bribery and backhanders is indeed true, and if the perpetrators get away with it, it will establish a pattern akin to Nigeria in the 1970s, 1980s and 1990s, where corruption became a pivotal feature of the economy. 

Why could this probe turn out to be a litmus test for the ANC? Because it will determine whether the ruling party has the political will to root out corruption in government even when some favoured sons and daughters may be among the targets. 

If the stakes for SA are indeed this high, the investigation process calls for close monitoring by the public over the next few months. Several things should be watched. There have been reports emphatically denied that Minister in the Office of the President Essop Pahad and ANC chief whip and former defence committee chair Tony Yengeni have been attempting to scupper the entire investigation. In reality, that seems unlikely. Pahad and Yengeni would surely not have been so foolish as to attempt anything so crass either out of a misplaced loyalty to President Thabo Mbeki (whose brother, Moeletsi, has been linked to the arms package), or in an attempt to preserve their own reputations. 

The best interests of all those individuals tarnished by rumour and suspicion must surely lie in an investigation that clears their names. The same applies to government as a whole, as Deputy President Jacob Zuma and Defence Minister Mosiuoa Lekota, who have consistently backed the probe, appear to appreciate. 

Investigators need to treat with caution the flood of allegations emanating from sources like Patricia de Lille who, notwithstanding her attributes as an energetic politician, is after all a member of the opposition. The same applies to allegations made by lobby groups opposed in principle to the package. They have a strong interest in orchestrating doubts about its efficacy. But there seem to be other sources of evidence of corruption.

There will be no crass scrapping of the investigation. However, there may be attempts to weaken it. There are two particular straws in the wind that could indicate that this is happening. The first would be a narrowing of the scope of the investigation. Until last week, a development to watch out for would have been a presidential proclamation enabling Heath's unit to pursue its side of the investigation. 

Some will argue that the Constitutional Court has saved anyone at the presidency who may have had reservations about Heath's participation. But that is not so. The court has given government a year to replace Heath. There is nothing in its judgment to suggest that his unit may not be given one last proclamation in the meanwhile. One way for the presidency to demonstrate it is co-operating fully with the probe would be to empower the unit to participate in this probe. 

A second straw in the wind relates to the role of the public accounts committee, which is chaired, as is traditional, by an MP not of the ruling party, in this case Gavin Woods of the Inkatha Freedom Party. The committee's courageous efforts should be applauded by all within the ANC and without who value good governance. But though it has the backing of Zuma and Lekota, the committee, and particularly its ANC members, have angered important folk in the ANC. 

So the second danger signal to watch for is whether the committee is forced to withdraw from overseeing the investigation. The rules of Parliament spell out the committee's powers. The committee on public accounts "must consider any reports issued by the auditor-general on the affairs of any executive organ of state, constitutional institution or other public body; and may initiate any investigation in its area of competence". It would be well to watch for any interpretation of these powers designed to clip the committee's wings. In particular, we should be watching to see whether any powers that be put out the message that the committee has fulfilled the role designed for it and that it should now withdraw.

If that, or anything similar happens, prepare for a trip down the Nigerian road. If the probe proceeds effectively, and ultimately nails some well-known names, be grateful you are living in a country ruled by a government committed to wiping out corruption.

With acknowledgement to Alan Fine and the Business Day.