But the differences were concentrated in the central pattern areas. The peripheral ridges — the areas toward the outer edges and margins of the fingertips — retained sufficient clarity for comparison. The surviving ridges showed pattern characteristics consistent with the known Dillinger record. Harold Cummins, a fingerprint expert who analyzed the case for a 1935 academic publication, reported that the acid damage was concentrated in the central areas, while the extensive portions of the fingertip surfaces that had not been damaged bore enough ridge detail for identification purposes.
The formal conclusion of the FBI identification was positive: the postmortem fingerprints, notwithstanding the acid-induced alteration of the central pattern areas, were consistent with the known Dillinger fingerprint record. The dead man was John Dillinger.
Nuclear DNA comparison — which could definitively settle questions of this kind — was not available in 1934; the science would not exist for decades. The FBI’s identification rested on fingerprint evidence, family identification (Hancock’s positive identification and the elder Dillinger’s ambiguous response), the circumstantial convergence of evidence placing Dillinger at the Biograph, and the testimony of the agents who recognized him emerging from the theater.
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## The Autopsy and the Disputed Details
The formal autopsy of the body was conducted at the Cook County morgue. The report, which disappeared from official records for approximately fifty years before being found in 1984 in a shopping bag at the old morgue, recorded various findings about the body.
Some of those findings became sources of controversy in later years. Critics of the official identification noted a series of potential discrepancies: