Was Dennis Regan an Accomplice?
Dennis Regan lived at 112 De Koven Street, about a block away from the O'Learys. He testified that while in bed he heard one of the neighbors say that the O'Leary barn was on fire. He jumped out of bed, ran to their home, and attempted to save their wagon and put out the fire.
In order to give credence to Regan's testimony, this neighbor would have had to discover the fire even before the O'Learys did. This seems highly improbable. Also, Regan stated at the inquiry that while passing the McLauglin home he heard music. Yes, there was music during the McLauglin party--but Mrs. McLaughlin testified that the fire started after the music stopped. Regan's testimony consists of only four and a half pages--but these few pages contain inconsistencies that almost rival the discrepancies found in Sullivan's twenty-one pages of testimony.
The evidence that most exonerates Mrs. O'Leary is, in the final analysis, the most damning to Sullivan and Regan. As noted earlier, at the time the fire broke out, there was no reason for anyone to believe that it would be of any great consequence. Therefore, the person responsible for the fire would most likely, upon its inception, attempt to extinguish the fire and save the O'Leary animals and property--this Sullivan and Regan did. Failing that, this person would next alert the O'Learys--this Sullivan and Regan did. Because of their incriminating behavior, and because of their equally incriminating testimony, it seems reasonable to theorize that Daniel "Peg Leg" Sullivan and Dennis Regan--and not Mrs. O'Leary and her cow--may have been responsible for the Great Chicago Fire.