His fourth book, 'Then the Walls Came Down: A Prison Journal' (1999), was described in the Irish Times as 'remarkable as a human document' and compared it to Brendan Behan's 'Borstal Boy'. Another review in the same newspaper called it 'one of the most important books to emerge from the conflict in Northern Ireland... a vividly humane account of life in prison. 'The Observer commented that in 'post-ceasefire Northern Ireland...the new thinking has come from those involved in the republican war. Danny Morrison's prison memoirs in an honest study of a man seeking fresh solutions to the stalemate the Provos found themselves in at the beginning of the Nineties.' The Irish News said it was 'invaluable as a rare look at prisoners as human beings.'