Much has been written about the Diplock Court system. The courts relied heavily on confessions. This stimulated much concern and probably encouraged unacceptable interrogation techniques with the attendant risk of miscarriages of justice.
An interesting and detailed study - "War on Terror: the lessons from Northern Ireland" - may be read here. It is quite lengthy but well worth a read by the student wishing to form a more in depth knowledge.
Addendum 16th October 2010: Given that this post ought to remind us of the value in society of the jury, it was interesting to read an article by Jon Robins (Guardian 13th October) - "Ricin Trial ullustrates the importance of juries."