Hanratty - The Final Curtain

Sixty years ago a small time thief, James Hanratty, with no history of violent crime was hanged for a motiveless and horrific murder, but vital evidence, withheld from the original trial, indicated that he might have been wrongly executed.
His defence counsel couldn't take it in that this evidence had been concealed.
At the same time, new DNA discoveries by forensic scientists told a very different story.
If the interpretation of the DNA was right then James Hanratty was guilty, but if other new evidence, kept secret from the trial was right, then he might be innocent.
What is the truth in this case?
Was he innocent or guilty?
Is this DNA evidence a cover up for the British government?
Is this the final curtain on the James Hanratty case?
What is your opinion after reading this book?