Henry Kendall had a sharper eye than most. It was a skill that stood him in fine stead in his profession as a maritime Captain. But, on this occasion, it wasn’t his ability to locate and avoid fellow vessels or rocky outcrops that would catapult him into the public eye.

As his ship, the SS Montrose, was ploughing a spume-flecked furrow towards Canada in the summer of 1910, Kendall noticed something odd about two of his passengers.

Registered as Mr and Master Robinson, it seemed to Kendall that these first class passengers were not father and son at all. “Three hours after sailing my attention was attracted to two persons. When I saw the boy squeeze the man’s hand I thought it strange and unnatural,” he later told police.

Now certain that Master Robinson was, in fact, an adult woman, Kendall used the nascent Marconi ship wireless telegraph to contact Britain: “Have strong suspicions London cellar murderer and accomplice among saloon passengers,” he radioed to shore. It was this message that enabled Scotland Yard to meet the Montrose in Canada and promptly arrest the couple.

Dr Hawley Harvey Crippen and his lover Ethel de Neve had been caught.

“This is the archetypal English murder case. I knew new DNA evidence had opened an intriguing mystery right at the heart of it, but I had no reason to think that the architecture of the case built around it wouldn’t still be sound.

“I was stunned at what I found when I started digging into it.”

So says the author Matthew Coniam, whose new book explores gaping flaws in the original trial of the notorious Dr Crippen, while also delving into fresh DNA evidence which, over a century on from the American homeopath’s execution (he was never qualified to practise as a doctor in the UK) renders the most vital piece of evidence against him as entirely invalid.

The discovery of a body at Crippen’s home on Hilldrop Crescent in Kentish Town in 1910 was damning.

Police, and later the jury, considered it to be incontrovertible evidence that the “doctor”, locked in a loveless marriage with Cora, an unfaithful opera singer, had murdered her in order to be with his mistress Ethel de Neve.

Crippen had, so it was declared in court by the pathologist Dr Bernard Spilsbury (whose word was considered gospel in cases of this nature), chopped up and filleted his wife, leaving parts of the body buried under piles of coal in the basement of the property.

While what were believed to be Cora’s mutilated remains were mouldering in North London, Crippen, with Ethel in tow disguised as his son, beat a hasty path on to a ship that sailed first for Belgium and then to Canada. The sensational pursuit of Crippen by sea and his subsequent execution made his name a by-word for the quintessential domestic murderer.

Yet, as Matthew contests, long before DNA evidence came into play, some 97 years after the case, there have long been holes in the story of Crippen and the murder of Cora.

“Why did Crippen do nothing to cover his tracks, before and after,” asks Matthew.

“Why did he leave some of the flesh in the cellar of his house if he had managed to get rid of the vast majority elsewhere?

“Why did he bring suspicion upon himself by flaunting Ethel de Neve in his wife’s jewels and furs? The onus is still on the prosecution to account for those things, and they don’t have anything convincing to offer.

“But I also discovered it was simply impossible for Crippen to have done all the things he is supposed to have done in any kind of realistic time frame.”

Protesting his innocence until the end, the already sizeable weight of evidence against Crippen being guilty of Cora’s death was magnified in 2007 when DNA technology was applied to the mutilated remains, which remarkably had been preserved in London.

US forensic pathologist John Trestrail discovered the remains conclusively belonged to a male. So if it wasn’t Cora, whose remains did the police find when they searched Crippen’s house?

And is it possible the body parts could have been planted by the police in order to secure a conviction?

“That’s impossible to say, given the layers of confirmation bias that cloaked it at the time,” Matthew reflects.

“Nothing would surprise me. At this distance, my best guess would be that the remains came from an anatomy lab.

“The police thought it was just a marital dispute and if the remains hadn’t been found it would probably have all just faded away. It was the discovery of the body parts that made the sensation and started the manhunt.

“I can’t imagine Scotland Yard risking its reputation to concoct something so elaborate in those circumstances, but I do think they gingered up the find with planted secondary evidence, however.”

As to what happened to Cora, Matthew contends Crippen was telling the truth when he told the authorities he believed she had gone to America.

“Crippen was uselessly and suicidally telling the truth. I think Cora may well have gone to America to plant herself on her half-hearted lover, Bruce Miller. It now seems plausible that Crippen’s major mistake was fuelled by social embarrassment at Cora leaving him, as she had threatened to do so many times.”

Lying about her whereabouts and then jumping on a ship to Canada may have felt to Crippen like his only escape from a future of being excluded from his own corner of London society.

But his lies were immediately taken to be those of a murderer rather than those of a mundane man whose wife had walked out on the marriage.

Yet more unanswered questions arise. If Cora was alive all along, why didn’t she come forward? Some 16,000 people petitioned the Home Secretary of the time, a certain Winston Churchill, for the execution of Crippen not to go ahead.

In among the letters were a handful that claimed to be from Cora herself, claiming she was alive and well and that her husband was innocent.

Presumed to be from a hoaxer they were ignored. Perhaps, as Matthew concludes, Crippen, rather than being one of the first criminal masterminds of the media age, was just a man who chose to flee across the Atlantic when staying put in humble North London might have saved his life.

“He was certainly unlucky – maybe the unluckiest man of all time,” concludes Matthew. “But his actions only seem foolish if one starts from the presumption that he was guilty.

“Imagine him to be exactly the person he claimed to be, then everything he did makes perfect sense.

“He would have thought that getting away and starting again somewhere they weren’t known was the most sensible thing to do. And there certainly would’ve been a great manhunt if it hadn’t been for the chance discovery in the cellar. If he hadn’t fled the country then he would have made a much more convincing account of himself.”

• Mr Crippen, Cora And The Body in the Basement by Matthew Coniam (Pen & Sword Books Ltd, £25). Order a copy for £25 at expressbook shop.com or call 0203 176 3832. Free UK P&P on online orders over £25