In Julius Caesar, Brutus is an honorable man. He admits that he loves Caesar, but he loves Rome more. Brutus puts his reputation on the line when he joins the conspirators. He stabs Caesar along with the conspirators. In fact, Caesar's last words indicate the love and respect that even Caesar had for Brutus. When Caesar cries, "Et tu Brute?" meaning "Even you Brutus?" Caesar responds, "Then fall Caesar."
Caesar believed in Brutus so much until he exclaims that he must die if Brutus thinks he must die. Brutus is honorable and he puts himself at risk by killing Caesar.
In much the same way, Atticus is a well respected man in the community. He, like Brutus, puts himself at risk by defending Tom Robinson. People of the community call him a nigger lover. In reality, Atticus is trying to make sure that justice is served. He believes in Tom Robinson, and he presents a great defense for his client.
Brutus and Atticus are both well respected. They both put their reputations at risk by standing up for what they believe in. They both lose friends because of their stand. They both live in a society that does not support justice and fairness. Ultimately, they both lose the battle in their stance on fairness and justice.