1.   Several politicians and reporters have compared Kovalev to Andrei Sakharov, the physicist, Nobel laureate and persecuted dissident from Soviet days.

2.   Past authoritarian governments used it to persecute dissidents, including President Kim Dae-jung, a former opposition leader and pro-democracy activist.

3.   China has continued to persecute dissidents after the massacre, and many have fled to the West.

4.   Police have in recent years increasingly used common criminal charges to persecute political dissidents.