Last week, the Constitutional Council upheld a complaint against Christian Estrosi, the Gaullist deputy for Nice's second constituency, formerly held by Jacques Medecin, the fugitive former mayor.
It said the activities of an organisation called 'The Friends of Christian Estrosi' should be counted as part of his campaign in last March's National Assembly elections. This took his expenses above the permitted 500,000 franc ( pounds 57,000) limit, bringing automatic disqualification.
Mr Estrosi, 38, formerly the deputy for another Nice seat, moved in the last election specifically to fight Jacques Peyrat, a well-known lawyer who is the National Front's most popular figure locally. In the first round, Mr Peyrat was ahead of Mr Estrosi, but the Gaullist squeaked into the lead in the run-off vote.
The decision against Mr Estrosi adds another element to what promises to be interesting months ahead in Nice. Last week, Mr Medecin, detained in his Uruguayan exile last month, was formally notified of an international arrest warrant against him. If Mr Medecin, who fled France in 1990 to avoid corruption charges, is expelled and returns to face charges, this will create an uproar in a city where he remains popular.
In municipal elections in 1995, Mr Peyrat had been expected to try and take Nice city hall, now held by the Gaullist Jean-Paul Barety who succeeded Honore Bailet, Mr Medecin's immediate successor. Mr Bailet resigned in October after his wife was charged with receiving and his stepson charged in a murder case.
One way the Gaullists could fend off the far-right challenge is for a big name to stand in the constituency. The new election has to be held before mid-March. The leading Gaullist most often mentioned is Jacques Toubon, a native Nicois and the Culture Minister. Although rumoured to want to make Nice his fief, he has given no public indication of this.Reuse content