The strongest case has always been against Kominski. Sir Robert Anderson, then the lead investigator, wrote in his memoirs that the police knew that Kominski was Jack, but they had no case and Kominski was safely lick away in an insane assylum.
The police also had an eyewitness to the killings who IDed Kominski for police when Kominski was under care but the witness stated that he would not testify under oath because Kominski was a Jew and so was the witness. At the time of the slayings, the Jews were hated by the general population, and everyone knew that it was a powder keg and if the populace knew a Jew did it, all hell, and full scale rioting and slaughter would take place.
I seem to recall something about the apron but haven't found it yet.