Justice Rossiter was the Governor of Kozepén on Világ. He took a shine to Evelyn Smythe when they first met. Evelyn later became his special advisor. After they became close, he asked her to leave the Sixth Doctor.
In the year after the Killoran invasion, he was promoted to Principal Triumvir, and was given responsibility over all three countries on Világ, now combined and called the Triumvirate. When Evelyn returned to the planet, she decided to stay with Rossiter.
Three years after the invasion, when the Sixth Doctor and Melanie Bush arrived to visit Evelyn, Rossiter wanted to go with the Doctor to discover where the terrorist had taken Evelyn. He helped the Doctor to search a hospital ward with catatonic patients. After looking at some files, he realised that they were under his daughter Sofia Rossiter's hospital. (AUDIO: Thicker Than Water)