My son was arrested in a case of drug trafficking with crypto. How long can investigation last?

Hello Sir

My son is trading in cryptocurrency, online trading, and Binance exchange, with no personal contact.

A  drug dealer purchased crypto & used that money for drug trafficking. So the police arrested my son also and the investigation is under process.

What is the maximum time for investigation and when will it be transferred to the court?

How much time will it take?