I had. difficulty. working. out. who. was. the. killer. was. However. I. did. enjoy. reading. the. autopsy. reports. at. the. back. of the. book. l. think. it. should. be. remembered. that. DNA. fingerprinting. wasn't. available. in. 1966. DNA. fingerprinting. was. discovered. by. accident. by. Mr. Alex. Jeffrey's. a. professor. of. genetics. at. Leicester. University.