Though he is not the first modern head of state in the dock – his predecessor and political mentor Jacques Chirac was convicted of embezzlement – Sarkozy is the first to face corruption charges.
He fought furiously over the past six years to have the case thrown out, and has denounced “a scandal that will go down in history”.
“I am not a crook,” the 65-year-old, whose combative style has made him one of France's most popular rightwing politicians, told BFM TV this month.
Prosecutors say Sarkozy promised the judge a plush job in Monaco in exchange for inside information on an inquiry into claims that Sarkozy accepted illicit payments from L'Oreal heiress Liliane Bettencourt for his 2007 presidential campaign.
Their case rests in large part on wiretaps of phone conversations between Sarkozy and his longtime lawyer Thierry Herzog, which judges authorised as prosecutors also looked into suspected Libyan financing of Sarkozy's 2007 campaign.
That inquiry is still underway, though Sarkozy caught a break this month when his main accuser, the French-Lebanese businessman Ziad Takieddine, suddenly retracted his claim of delivering millions of euros in cash from Libyan dictator Moamer Kadhafi.
Sarkozy and Herzog have assailed the taps on their phones as a breach of client-attorney privilege, but in 2016 a top court upheld their use as evidence.
Charged with bribery and influence peddling, Sarkozy risks a prison sentence of up to 10 years and a maximum fine of €1 million.
Herzog, a leading member of the Paris bar, faces the same charges as well as violation of professional secrecy. The trial is expected to last three weeks.
Investigators discovered that Sarkozy used an alias – Paul Bismuth – to buy a private phone for conversing secretly with his lawyer.
On around a dozen occasions, they discussed reaching out to a top French judge, Gilbert Azibert, a general counsel at the Cour de Cassation, France's top appeals court for criminal and civil cases.
Prosecutors say Azibert, who is also on trial, was tasked with trying to obtain information from the Cour de Cassation lawyer in charge of the Bettencourt inquiry, and to induce him to seek a verdict in Sarkozy's favour.
In exchange, Sarkozy would use his extensive contacts to give “a boost” to Azibert's efforts to secure the cushy Monaco post.
“He's been working on it,” Herzog tells Sarkozy in a call from early 2014.
Azibert was already considered a leading candidate for the job, but “if you give him a boost, it's always better,” Herzog says in another.
“I'll make him move up,” Sarkozy tells Herzog, according to the indictment by prosecutors, who compared his actions to those of a “seasoned offender”.
But later, Sarkozy tells his lawyer that he would not “approach” the Monaco authorities on Azibert's behalf — a sign, according to prosecutors, that the two men had been tipped off about the wiretaps.
“Mr Azibert never got any post in Monaco,” Sarkozy told BFM television this month – though under French law, just an offer or promise can constitute corruption.
Still in limelight
Sarkozy, a lawyer by training, has long accused the French judiciary of waging a vendetta against him, not least because of his attempts to limit judges' powers and criticism that they are too soft on delinquents.
He will again be back in court in March 2021 along with 13 other people over claims of campaign finance violations during his unsuccessful 2012 re-election bid.
Prosecutors accuse Sarkozy's team of using a fake-invoices scheme orchestrated by the public relations firm Bygmalion to spend nearly €43 million on the lavish run – nearly twice the legal limit.
The long-running legal travails hindered his comeback bid for the 2017 presidential vote, losing out as the rightwing nominee to his former prime minister François Fillon.
Yet like other former French presidents, Sarkozy has surfed a wave of popularity since announcing his retirement from politics in 2018, pressing the flesh with enthusiastic crowds at his public appearances.
Lines of fans queued over the summer to have him sign his latest memoirs, “The Time of Storms”, which topped best-seller lists for weeks.