Why is juror 3 a villain?

Juror Three is seen as a villain because of his refusal to listen to the evidence and make an unbiased vote on the defendant's guilt. He is descibed as a bully, he is physically abusive, and his views are greatly swayed by his currently nonexistent relationship with his own son. Though he is the last juror to cast a vote of innocence, he does eventually come to realize that his anger and desire to convict the defendant is all tied up with the feelings he has for his son.