How was imprisoned neo-Nazi leader able to communicate with out-of-state inmate in alleged power grid attack?

Brandon Russell and Sarah Beth Clendaniel are accused of plotting a sniper-style attack on several electrical substations in the Baltimore area. 

Russell founded a Florida-based neo-Nazi group and was on the Federal Bureau of Investigation’s radar. In 2017, he was sentenced to five years in federal prison for having an unregistered destructive device and storing explosive material in his apartment.

A year later, while Russell was in a Florida prison and Clendaniel was locked up in another state, the two started communicating with each other through an encrypted messaging app, according to Fox News.

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"There are pretty limited circumstances in which a federal inmate can correspond or communicate with another federal inmate or another state inmate," Chris Zoukis explained. 

Chris Zoukis should know.  He spent 12 years in federal prison and now runs a consulting group. "It could be direct, the two inmates involved here could be directly communicating like through contraband cell phones or they may have pegged a person outside of prison that was being their conduit like someone who was forwarding communications back and forth," Zoukis continued.

According to the Federal Bureau of Prisons' website, inmates are only allowed to write to each other if they are immediate family members, or they are both involved in the same legal case.