What Herbert ??? (Unnecessary)
Answer: Simply because he believes that someone has to fight for Tom, and no one else would do it.
Explanation:
Atticus was not only defending Tom Robinson in the case, but also against all the racist people who believed he was guilty just because he had coloured skin. Atticus was trying to show her daughter that some causes, though lost, should be defended.
Giving the source credit in a footnote or endnote
