A: Why did you quarrel with our teacher?
B: He held a brief for Tom, it's unfair.
A: Don't tell me that. I think you were wrong, too.
hold a brief for
exp. To be able or unwilling to tolerate or support someone or something.（为......辩护，有意维护......）
e.g. The boss held a brief for his assistant who had done wrong.
e。g。 I would rather be laughed at than quarrel with him。
e.g. It's very sad when husbands and wives quarrel with each other.