These form by getting caught in the crashing waves near the edge of a beach forcing them to continually spin over and over and over, leading to a more spherical look.
It's a pebble that must have been tumbled downstream, banged and smoothed against other stones as it went, in the process that geologists poetically describe as 'chattering'.
But writing legislation which protects ordinary people yet does not constrain the press's freedom is hard-witness the experience of France, which has a privacy law and a tradition of excessively tactful newspapers.