Former Montgomery County, Md., homicide Detective Rich Fallin wants to made it clear he is on the outside looking in and does not want to second-guess Fairfax County, Va., investigators, but he has some strong gut feelings as to who investigators might be profiling as Pham's killer.
The rising college sophomore was stabbed and killed in broad daylight and was found behind the wheel of her car near Route 50 and Williams Drive.
Fallin believes the fact that Pham was stabbed suggests the killer may have been a woman.
"Women tend to like to use knives," he said. "A man wouldn’t have to use force. He wouldn’t have to stab her so many times. A man might be more willing to cut her throat and choke her."
Fallin also noted the tight timeline leading up to Pham's death:
That short window of time suggests to Fallin that someone may have been angry with Pham and hid in her car.
Fallin also theorized that the killer may have been someone Pham knew.
He also believes the killer has been lucky and that someone probably saw the killer and didn't realize it.
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