The decision by Zimbabwe's Supreme Court to overturn an electoral amendment introduced by President Mugabe will allow the opposition to challenge the validity of more than 30 seats in parliament.
Mr Mugabe had introduced the amendment last month in order to prevent any challenge to the results of last June's election. The court's ruling presents him with the options of complying with the rule of law or defying the highest legal institution in the country.
It is a rather sad situation in which Mr Mugabe finds himself. Having triumphed over reactionary attempts to block the introduction of democracy in what was then Rhodesia, his early work as a political leader was met with no small measure of success.
Those who predicted a collapse in the economy were proved wrong. For a considerable period of time Zimbabwe prospered. It became a beacon of hope for other countries in sub-Saharan Africa which were struggling for their very survival.
In more recent years, however, the tide has turned against the president and his country. At present an energy crisis bedevils Zimbabwe, the economy is in a parlous state and the political instability resulting from last summer's violent and divisive election campaign has served to thwart any meagre hopes of recovery there may have been. More than 30 people have lost their lives and an estimated 13,000 people were forced to flee their homes in the course of that campaign. Most of them were opposition supporters.
Zimbabwe's commitment of men and materiel, at great expense in lives, equipment and money, to the internal conflict in Democratic Republic of Congo (formerly Zaire) has been a drain on resources at a time of great need. Efforts by the European Union to broker a ceasefire which would involve the installation of a United Nations peacekeeping force are, while welcome in themselves, likely to be too late to have a beneficial effect on Zimbabwe's struggling economy.
A great deal has been made of the occupation of private farms by Mr Mugabe's supporters. Attempts to redistribute land are not without justification. Many of the vast tracts which form commercial farms today were taken by force without any consideration for traditional rights. However, an attempt to install landhungry people without training in farming methods has led to under-utilisation of resources and civil strife between white farmers and supporters of the president. The suggestion that these attempts have been made - not to provide the dispossessed with land - but as a cynical measure to boost Mr Mugabe's personal support, carries with it an inescapable logic.
The opposition needs to win only three of the 38 contestable constituencies to gain a majority of the elected seats in parliament. The court's decision provides it with an unprecedented opportunity to do so. There may be some temptation for Mr Mugabe to defy the ruling. He would do a service to his country and to Africa were he, instead, to fight any proposed by-election in a dignified and democratic manner without resorting to intimidation or misuse of the emotive land issue.