A hearing began Thursday for criminal defence lawyer Hal Mattson, who is charged with obstruction of a judicial proceeding.

A publication ban is in effect for the preliminary hearing, so no details are available on the proceedings in court.

Mattson is accused of trying to influence a witness in a separate case. He was represented by a Toronto lawyer during the hearing.

Mattson has been practicing law for 27 years and his family was also in court to support him.

While he has seen his clients through countless cases, Mattson tells CTV News being the defendant rather than defender is a new and difficult experience.

"Well it's just a lot of stress on my family and myself. Sometimes I don't think the people understand that subconsciously the difficulty of going through the criminal justice system causes a lot of problems that you're really not aware of."

The crown attorney, who was brought in from London for the case, did not want to comment.

The hearing resumes Friday.