Since you are entangled within the legal system, its best for you to remain abstained until your legal troubles are over.

To answer your question, nobody can realistically give you an answer as to how long it takes for you to be clean after one smoking session. Each persons body is different and there are too many variables to take into consideration to arrive at an estimate. Only periodic testing with a THC test kit (using the first urination of the day for each time) can give you that answer.