Aaron Kosminski is one of only two suspects (the other being Joseph Barnett) against whom there is real evidence or testimony. The case against Kosminski is stronger than many of us who believe in alternate theories are generally prepared to admit -- it is even stronger than those who suspect Kosminski usually dare to argue. In particular, those who suspect Kosminski elevate the opinions of Dr. Robert Anderson to such Olympian heights that newcomers can get the impression Kosminski is only important as "Anderson's Suspect." In fact, Kosminski makes a perfectly respectable suspect whether or not Anderson ever heard his name.
Swanson
Aaron Kosminski should properly be called "Swanson's Suspect" as it is clear from the wealth of detail he provides that it was Swanson, not Anderson, who personally arranged the lineup where an eyewitness allegedly identified him. As Swanson's favourite witness was Lawende, it is virtually certain that Kosminski was suspected of the Eddowes murder in Mitre Square.
Anderson
Eventually (1910) accepted the Kosminski solution, based on the evidence of Swanson's Witness (probably Lawende, see above.) In 1908 he gave an interview implicating Barnett. Who he suspected at the time is controversial. Melvin Harris cites contemporaneous notes that he had no suspects at all, but the Stephen White story says Anderson favoured "a young Jewish medical student."
Watkins
It is now established that PC Watkins was the "City PC near Mitre Square" who is quoted by both Sims and Macnaghton as seeing a man resembling Kosminski flee the scene of the Eddowes murder.
Sims
Journalist covering the murders indicates 3 suspects, one of whom is believed to be Kosminski. This suspect "had at one time been employed in a hospital in Poland." If Kosminski was a former medical student, he could have been the man Anderson favoured from day one, regardless of his later comments about Barnett.
White
Sgt. Stephen White encountered a suspect he described as tall, thin and cultured, probably near Dutfield's Yard on the night of the double event. It was this description that supposedly gave rise to Anderson's suspicion of a young Jew. Was this man Kosminski?
Smith, Major
Major Smith wrote in his memoirs: "After the 2nd crime I sent word to Sir Charles Warren that I had discovered a man very likely to be the man wanted." Smith's Suspect was a man "who had been a medical student." Smith characteristically omits any mention of race or religion, but it seems likely that this is yet another reference to Kosminski, as he once worked in a hospital, and there are few suspects who were "very likely" to be "the man wanted." Sugden's choice of Dr. John Orford must be wrong. To refer to the Senior Resident Medical Officer of the Royal Free Hospital as a man who had been a medical student would be an absurd understatement. Smith cleared this suspect by proving his Hanbury Street alibi "without the shadow of a doubt." If Kosminski had an alibi for the Chapman murder, he can't be Jack whatever Lawende thought he saw.
Smith, Emma
A story on the internet claims Emma Smith actually named "Aaron Kosminski" as her attacker before she died. Due to serious discrepancies in m.o., Smith is no longer considered a Ripper victim by most historians. If this is the crime of which Kosminski was accused, he is unlikely to have been the Ripper. For one thing, Swanson's Witness would have to be someone other than Lawende.
Macnaghton
The Macnaghton Memorandum lists Kosminski as one of the final 3 police suspects, with Ostrog and Druitt. Macnaghton likes Druitt, but only because of "private info" i.e. family gossip. This list is probably the document Sims saw in researching his articles -- making it probable that the Polish hospital worker was Kosminski.
The perceptive reader will have noticed a problem in all this. The contemporary sources who suspected Aaron Kosminski or someone like him contain a major contradiction about what he looked like! If Kosminski was Jack the Ripper, then he was slender, almost six feet tall, spoke English with cultured manners and had strange, glowing eyes (White's description) and he was no more than 5'7", of medium to stout build with "the appearance of a sailor" (Lawende's description.) Could Kosminski's appearance have changed so much between the White sighting and Swanson's lineup? Possibly. But there is a disturbing possibility that all 3 of Macnaghton's final suspects were thoroughly confused with each other. Consider: Kosminski's hospital experience is falsely attributed to both Ostrog and Druitt. A medical kit most likely inherited by Druitt from his father is falsely attributed to Ostrog. Ostrog's description is falsely attributed to Druitt. (See the Sims page, where the Ripper is said to be a Sims lookalike who drowned after the last murder. Only Druitt drowned; only Ostrog resembled Sims.) White's description of a man resembling Druitt is taken by Anderson as a sighting of Kosminski. And Druitt's suicide is used to explain the "mysterious disappearance" of any suspect the police can't find -- including Tumblety! We may never know which one of these men, if any, was the one and only Jack the Ripper.
