BESANCON, France (AFP) — A French doctor who goes on trial Monday accused of intentionally poisoning 30 patients, 12 of whom died, sounded defiant in a radio interview before the hearings opened, saying he was not responsible for the “distress” of his alleged victims and their families.

Frederic Pechier, 53, worked as an anesthetist at two clinics in the eastern city of Besancon when patients went into cardiac arrest in suspicious circumstances between 2008 to 2017. Twelve could not be resuscitated.

Pechier is accused of triggering heart attacks in child and adult patients in an alleged attempt to show off his resuscitation skills and discredit co-workers.

Pechier’s youngest alleged victim, a four-year-old identified as Teddy, survived two cardiac arrests during a routine tonsil surgery in 2016. The doctor’s oldest alleged victim was 89.

The trial caps a seven-year investigation that stunned the medical community. Pechier has denied the charges.

Speaking to broadcaster RTL early Monday, Pechier said “It’s necessary to lay all the cards on the table,” adding that he had “strong arguments” in his defense.

Asked about the suffering of the families who will attend the trial, set to last until December, Pechier replied: “I understand it completely, but on the other hand, I am not responsible for their distress.”

Pechier, a father of three who has been banned from practising medicine, faces life imprisonment if convicted. He is not currently behind bars but under judicial supervision, an alternative to pre-trial detention.

“I’ve been waiting for this for 17 years,” said Amandine Iehlen, whose 53-year-old father died of cardiac arrest during kidney surgery in 2008.