The "swatting" conspiracy involved more than 250 victims, about $250,000 in losses and disruption of telecommunications service and emergency personnel.
Getting tactical teams deployed on fake emergency calls is known as "SWATing."
Guadalupe Santana Martinez in March was sentenced to 21/2 years in prison.
Sentencing is June 5 for Angela Roberson.
The five in late 2007 pleaded guilty to various charges, including transmitting interstate threats with the intent to extort, conspiring to use devices to modify telecommunications instruments and accessing protected telecommunications computers in fake emergency calls since 2002.