A rally planned for Mexico's capital city on Sunday could prove the defining moment in the complicated legal tangle involving Andrés Manuel López Obrador, Mexico City's popular leftwing mayor and presidential aspirant.
There are two possible outcomes. A big, non-violent “silent march” the mayor's strategists hope for 400,000 protesters would show the nation that popular support is not waning for Mr López Obrador, who faces arrest on a contempt-of-court charge. Demonstrations are planned throughout Mexico.
But a small turnout would confirm the difficulty he faces in keeping the issue of his political disenfranchisement alive in the minds of the electorate until next January, when nominations for the July 2006 presidential election close.
Two weeks after the Mexican Congress voted to strip him of his political immunity–a move that could bar the mayor from running for president–both sides still seem uncertain of their political momentum.
Polls continue to show that Mr López Obrador is the clear frontrunner in the presidential contest. The mayor denies he was in contempt of court during a 2001 planning dispute, and alleges that the congressional vote was a political manoeuvre engineered by President Vicente Fox to keep him off the ballot next year. The presidency maintains that the case is meant to demonstrate that everyone in Mexico, including elected officials, must maintain “strict adherence to the law”.
But the legal process is also proving much more complicated than expected. After the congressional vote, the Mexico City legislature which is controlled by Mr López Obrador's Party of the Democratic Revolution (PRD) said it alone should have the right to impeach the mayor.
The supreme court last week agreed to hear their constitutional challenge, catching the attorney-general's office off-guard.
At first the prosecutor's office reacted by announcing that an arrest warrant for Mr López Obrador would be postponed indefinitely to await the supreme court decision. Government spokesmen also floated, and then retracted, the possibility of a presidential pardon once the mayor had been found guilty.
Santiago Creel, the interior minister, also suggested that a political exit to the drama might be possible, but then said the solution would be left to the courts. Mr López Obrador even announced that he would return to work next week while waiting for the supreme court's decision although some said that doing so would amount to further contempt of court.
After days of intrigue, the prosecutor last Wednesday issued a warrant for Mr López Obrador to appear before a judge.
The judge, a 36-year-old former federal prosecutor, has until May 10 to decide whether the case is strong enough to proceed.
Two local legislators for Mr Fox's centre-right National Action party paid the mayor's 2,000 peso ($180, £95, €140) bail in advance, which would keep him out of prison. This surprised the mayor, who had advertised his intention to refuse to pay bail or appeal, so that he could go to prison at least briefly “as a political statement”. He called his unlikely benefactors “cheats, cowards and traitors”, and asked the judge overseeing the case to revoke the bail and allow him to go to jail.
Ruben Aguilar, Mr Fox's spokesman, said of the request: “It doesn't strengthen the republic, this strategy that tries to put things in reverse, where the accused tries to convert himself into the accuser and ask for apologies.”
With an untested legal process ahead, and with the mayor fielding a strong team of constitutional lawyers, however, the process remains unpredictable. But so far, Mr López Obrador is plainly perceived in the country as having right on his side.
Sunday’s demonstrations may indicate whether the mayor can maintain his high level of popular support until next July's election.
According to the most recent poll for the El Universal newspaper, 72 per cent of Mexicans believe Mr López Obrador was impeached to remove a political rival, rather than as part of a legal proceeding. Two-thirds said they would be prepared to take part in acts of civil disobedience to support him.
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