Bias

Perception:

Perception is the process of becoming aware of something through senses. For example: information taken in by senses from the environment (situation or circumstance or event or person or things or ourselves). Color of a car perceived by eyes, fragrance of a perfume perceived by the nose, taste of chocolate perceived by tongue, music perceived by the ears, a tickling sensation perceived by the skin.

Perspective:

Stepping back and viewing the situation or circumstance from different angles (for example, past memory, past experiences, feelings, other people's experiences).

Judgement:

This (perception) information is then evaluated and interpreted by the mind to arrive at a sensible decision or opinion or conclusion. This process after perception is called judgement. 

Biased perception:

A situation or event or person or things or ourselves are evaluated through a subjective lens influenced by past experiences, assumptions, preconceived, notions and pre-existing beliefs. It is an outcome of selective attention, screening, organizing, interpreting impulses (words, concepts, objects and individuals) and assigning meaning based on objective information. 

Biased perception then makes way for a biased unfair decision.