Rogers met his victims in bars, wooed them and moved in with them, Dixon said.
"Then one morning he would wake up and stab them to death," he said.
Of all his victims, he said, Rogers spent the least amount of time with the California woman, Sandra Gallagher of Van Nuys.
Dixon said he was able to prove five murders attributed to Rogers, who has been sentenced to death in California as well as Florida.
Asked why Rogers would now claim responsibility for the high-profile case, Dixon responded that he might be trying to get sent back to California.
"He could be getting close to execution in Florida," Dixon remarked. "They move faster there."
Dan Frazee, a retired sheriff's deputy from Clermont County, Ohio, questioned Rogers about a 1992 unsolved homicide. Rogers tried to make Frazee believe he had knowledge of the case when he really didn't, in hopes of going to Ohio, Frazee said.
"He's got nothing to do in prison right now but sit there and play games," Frazee said, adding that Rogers talked incessantly about death and murder and was "the most evil person I've ever talked to."
"It's like he has no soul," Frazee said.
AP Special Correspondent Linda Deutsch in Los Angeles contributed to this report.
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