Roberts was a technical worker on board Babylon 5.
After the attack on Shaal Mayan, Roberts was brought in for questioning by Chief Michael Garibaldi because he was in possession of a knife with fresh blood on it. When asked about it, Roberts claimed the blood was his because he had just recently cut himself opening a crate. With the Homeguard as the main suspect, Garibaldi asked if he knew who they were. Roberts not only knew who they were but agreed with their goals. Despite all this, Garibaldi booked him on a weapon charge but still let him go under red level surveillance. Later, when Commander Sinclair asks why he was released, Garibaldi explained that if the Homeguard was responsible for the attack on Mayan then Roberts would make a logical recruit for them, and that it would help security apprehend them in the end. With tensions running high amongst the alien population against the humans, Roberts is cornered by a pair of Drazi who attack and beat him badly. Luckily, security’s surveillance of him saved him from being killed. While in Medlab and still under surveillance, Roberts was visited by the leader of the local Homeguard chapter, Malcolm Biggs, speaking to him about the crimes of the “evil” aliens.