Hi, Cluciano63. I agree; with the number of CSi-style crime dramas crowding the air, it is a bit surprising. But most of these misfits live more for their macabre pleasure than for careful planning.
On a side question, has it been established that the serial killer used any of his victim's phones?
Yes:
A series of taunting phone calls made to the teenage sister of one of the victims calls that the police suspect came from the killer ...
And
Concerned, the Barthelemys pleaded with the New York police to help find her.
Then Amanda began to receive calls, about one each week, from her missing sisters cellphone.
Both Snipped from:
http://www.nytimes.com/2011/04/09/nyregion/09bodies.html?pagewanted=2&_r=1