The next 24 hours will help determine the fate of Telegram chief executive Pavel Durov, held in Paris for four days over allegations he allowed criminals to use the messaging app unfettered.

Under local laws, Durov’s detention can’t last beyond 8pm in the French capital - a total of 96 hours of police questioning. When that ends, the 39-year-old must be brought before an investigative judge at the Paris judicial court in the north of the capital.

The judge will then subject Durov to more questioning before deciding whether to press charges against him or name him as a material witness in the investigation and let him go free. 

Whisking him discreetly into court in a police van and interrogating him could take several hours - and French authorities could also decide to delay the face off with the investigative judge until the morning.

If charges are pressed, another judge known as the juge des libertés will likely have to rule on whether any limits should be placed on his movements or if Durov should post a bond. The entire process is expected to take place behind closed doors.

The legal drama comes just days after after the Russian-born billionaire was stopped at Le Bourget airport north of Paris on Saturday after disembarking from a private jet. Durov’s laissez-faire attitude to regulation made Telegram into a giant but also put him at odds with governments for repeatedly ignoring requests to better moderate content on his platform.

French authorities are looking into a wide range of allegations. They include refusing to help authorities run legal wiretaps on suspects, enabling the sale of child sexual abuse material and aiding and abetting drug trafficking.

In a statement released on Telegram on Sunday, the Dubai-based company asserted that Durov has “nothing to hide” and that the app abides by European laws.

“It is absurd to claim that a platform or its owner are responsible for abuse of that platform,” the statement declared. “We’re awaiting a prompt resolution of this situation.”

While the pressing of charges is a key point in French probes, a criminal trial - if any is ordered - may be several months or even years away. 

As the investigation progresses, Durov would have an opportunity to challenge any charges through his legal team.

  - Bloomberg