In the uniformed police ranks, an inspector wears two pips and a chief inspector three pips on each shoulder. Is there or has there ever been a rank wearing only one pip ? (such as a second lieutenant in the army)
In the modern Police Force, there is no rank with one pip, I googled this, and could find no record of there ever having been so, of cours, that doesn;t mean there hasn't been, maybe somone else can come up with something.