Let’s look at what another expert has to say about comparing someone speaking in a normal voice to someone screaming. This information comes from from Steve Cain. A little bit about him:
“Cain is president of Applied Forensic Technologies International of Chicago and Lake Geneva, Wisconsin, which specializes in voiceprint and audio tape analysis, tape authentication, polygraph examinations and analysis of questioned documents. He has more than 25 years experience in forensic science, including service as an agent in both the U.S. Secret Service and Internal Revenue Service. He was chief of the voiceprint units and senior document examiner for both the Secret Service and IRS as well as chief polygraph examiner for the IRS, with extensive courtroom testimony experience, including California’s notorious Hillside Strangler case.”
In an article that he wrote, called The Use of Voice as a Forensic Tool, he explicitly states:
“…it’s essential that speech samples contain exactly the same words and phrases as those in the questioned sample, because only identical speech sounds are used for comparison. “
So again, I ask how Tom Owen could possibly have made a credible determination about who was screaming from the voice samples he had available. Answer: He cannot.
Updated: Wagist.com has an excellent article up about Tom Owen, his software, and possible conflicts of interest.