The owner, licensee or operator of a visual or sound radio broadcasting station or network of stations, or the agents or employees of any such owner, licensee or operator of such a station or network of stations, or the owner, licensee or operator of a community antenna television system, or the agents or employees of any such owner of a community antenna television system, shall not be liable for any damages for any defamatory statement uttered over the facilities of the station, network or community antenna television system by or on behalf of a candidate for public office or by any other person. This section shall not apply to any such owner, licensee, operator, agent or employee who wilfully, knowingly and with intent to defame participates in the broadcast of a defamatory statement.