Mr. Farhan was detained for interrogation about his activities online back on December 10th, but he was never formally charged with any crime. He had been warned about his blogging before his arrest, but apparently his expressions of support of 10 men arrested by the Saudi government and labeled as terrorists is what prompted these actions by the police. Mr. Farhan's attorney said that the men were wanting to form a civil liberties group.
Considered the "godfather of blogging" in Saudi Arabia, Mr. Farhan was one of the first bloggers in that country to write under his own name. As the country is an absolute monarchy, many freedoms for press, public speech, and assembly are non-existent. His original detention was not reported to the outside world for three weeks, and word may never have been passed to people outside of the country if it wasn't for action taken by his friends.