This Britannian Police Commander was a commanding officer in the Britannian Police Force and was seen twice.
At Clovis Land, under Lelouch's Geass, the commander and his forces along with a Police Knightmare Frame Unit were ready to fire at Mao as they were ordered to shoot if he tries to expose Zero's identity. After Mao was angered by Lelouch as Lelouch said his lost, he was about to shout Lelouch is Zero. The Commander pointed his finger and yelled "fire!" which caused his forces to shoot Mao but didn't kill him since Mao got Britannian Medical Teams to save his life.
When Anya Alstreim the Knight of Six got her Knightmare Frame and tried to capture Lelouch at the Ashford Academy during a contest, the Police was called in. The Police Commander and his officers arrived at the academy but left afterwards because the problem was fixed.