Where an expert witness testifies to fingerprint analysis, testimony about the proper method used for analysis and identification is a substantive element of the testimony, and the testimony may be found insufficient to support a conviction if testimony that the proper method was used is not presented.The 1st District Appellate Court reversed the decision of Cook County Circuit Judge Vincent M. Gaughan.Tom Slowinski left his apartment at 8:15 a.m. on Sept. 1, 2015. When he returned, the front door was scratched and ajar …