Ross was a three-strikes-to-life inmate sent to Emerald City for dealing marijuana. He'd had an old crush of Diane Whittlesy, who was now working in Oz as a guard. He tried to get her to smuggle cigarettes in for him to sell, but Diane refused. Later, however, she changed her mind.
[Episode 05: "Straight Life"]

When cannibal Donald Groves got a tooth pulled, Ross suggested that he sell it. Ross also almost got into a fight with Muslim inmate Husseini Mershah after Ross insulted the Muslim ways.
[Episode 06: "To Your Health"]

Ryan O'Reilly and Ross got nervous that the Muslims may be planning a riot, and they debated where they would stand if something does happen.
[Episode 07: "Plan B"]

Diane approached Ross, saying that she doesn't want to bring him cigarettes anymore. Ross threatened to tell what she'd already done to the warden, which would get her fired and sent to prison. The riot did, indeed, break out, and Ross was selected as the leader of the Aryans and Bikers to be their representative on the council. Tim McManus (Diane's ex-boyfriend and unit manager of Emerald City) came into Emerald City to check on the hostages, and then volunteered to stay if they give up their wounded hostages and Diane. Ross made sure that Diane stayed as well as McManus. When the lights came off, Ross and the Bikers and Aryans lined up the hostages in front in case the shooting starts. When the shooting did begin, Ross took cover behind them.
[Episode 08: "A Game of Checkers"]