For weeks, I attempted to finish Patricia Cornwell's "Portrait of a Killer: Jack the Ripper, Case Closed" I haven't written a real book review, (or even been inclined to write one,) since High School English Lit., but this book frustrated me enough to write one.I've heard from many people what a wonderful piece of forensic investigation it is, how interesting, and that it seems the most plausible answer to the question of "whodunit."It must be confessed, that though I ordinarily like Patricia Cornwell's style of writing, and find her fiction very entertaining, I could not finish this book. It's just too big a fish tale to swallow. I just cannot finish a book that purports to have "solved" the case "100%" when every page is peppered with phrases such as "may," "could have been," "not saying absolutely," and "it seems likely..."This is not good investigation. This book is full of theories, based on assumptions, based on shaky premises, originating from a supposition that the man who produced such 19th and early 20th century dark and tawdry expressionist works such as the "Camden Town" paintings could actually have been the real killer. It is a theory that very few Ripperologists feel is even worth mentioning, aside from the fact that it has gotten a tremendous amount of media play since its 2002 publication date, even being made into a BBC documentary, (co-produced, naturally, by the heavily-invested, and completely biased Cornwell.)She relies strongly on 100 year old mitochondrial DNA, which, as far as I know, would not hold up well in a true prosecutorial case, especially as it does not particularly do anything more than exclude certain groups of people, thus potentially narrowing the field of suspects who licked stamps and envelopes. The fact is, there is no crime scene DNA known to be from Ripper, with which to compare her envelopes' mtDNA.I agree that Ms. Cornwell's high profile as a compelling crime-fiction writer, generates a predisposition to believe her suppositions. Her manner of "proof," however, throughout her "Portrait of a Killer" pages, begs her reader to agree with her subjective assessment of the psychopathology of Sickert's art as evidence of being the most likely, and indeed unassailable perpetrator of the Ripper serial killings.I don't buy it. It may be that she has a viable theory, but I am turned off completely by the shaky ground on which she builds her theory. She expects us to stipulate so much guesswork, in order to substantiate her case, (which, surely she has not substantiated, as there is very little substantive evidence in her guesses.)In her dedication, she arrogantly tells the Scotland Yard Detective, John Grieve, "you would have caught him." "HIM," I assume, referring to Sickert, as is her premise. Yet, try as I may, I cannot find any evidence that Det. John Grieve concurs with her conclusions. Does she, perhaps, toss his name about to lend credence to her ideas?This book makes me wonder if she decided on a suspect, then focused purely on gathering all the little bits of evidence that could lend credence to her ideas, while eliminating from her work all the bits of evidence that disprove her theories.I do have to give Cornwell this credit though... I had never bothered to look up any information on Jack the Ripper, prior to this book. I knew he was a British serial killer, I had seen parts of "From Hell," and other movies that fictionalize his crimes. Yet I had, (and admittedly still have,) little more a rudimentary knowledge of the case.My final opinion? Buy the book second-hand, and read it like fiction. You may find it entertaining. Then again, you may not. Better yet, I'll lend you my copy. It's only half used.