Former French President Nicolas Sarkozy is back on trial on Thursday for having allegedly spent twice the allowed amount in his failed 2012 election campaign.

Sarkozy, who was already  sentenced to three years in prison for a separate corruption case earlier this year, albeit without the prospect of serving time behind bars.He denies the charges in both cases.

The case restarted Thursday after being adjourned in March when one of the lawyers of a key witness took ill with COVID-19.

What are the charges?

Investigators opened the case after former deputy campaign director Jerome Lavrilleux described a system of fake invoices that allowed Sarkozy's conservative party the possibility of paying for lavish rallies.

"This campaign was a runaway train that no one had the courage to stop," said a Lavrilleux in a French TV interview in 2014.

Prosecutors allege that this allowed Sarkozy's party to benefit from a total of €42 million ($52 million) to pay for "spectacular and expensive rallies."

The allowed amount for election campaigns in France was only €22.5 million ($27.4 million).

Party members allegedly channeled the funds through a PR agency called Bygmalion to hide the increased costs.

Investigators have still not been able to prove Sarkozy organized or took part in the scheme, but said he must have known about the fraud.

A total of 12 other people, some who admitted wrongdoing, are also on trial for forgery, breach of trust, fraud and knowing of the illicit financing.

How has Sarkozy reacted to the charges?

Sarkozy, who was president of France between 2007 and 2012 and retired from politics in 2017, has denied the charges.

″Where is the money?″ he previously asked investigative magistrates, accusing others in the party of misusing the cash.

He said he does not remember two notes from accountants that warned him not to rack up extra costs for his campaign.

Despite these corruption scandals, Sarkozy's influence on politics continues to this day, with French media reporting he is currently advising current centrist President Emmanuel Macron.

What happens next?

Sarkozy might not be in court right away, but he has been ordered for questioning the week of June 14.

If convicted, he could face a year in prison and a fine of up to €3,750.

The case is known as the "Bygmalion affair," after the PR firm hired to allegedly cover up the fraud.

Sarkozy could also face further charges for taking money from Moammar Gadhafi and for influence peddling as a consultant for Russia.

The conservative party is now known as Les Republicains, although at the time it was called the UMP.

jc/rs (AFP, AP, Reuters)