A: Who will you guys keep for the part-time job?

B: The college kid who listens to his iPod all the time.

A: I thought you would hire the high school kid. He came with good references.

B: My boss didn’t want to hire him because he was still in high school. Apparently, he’d had a bad experience with a teenaged employee. To me, he tarred him with the same brush. Why did he blame him because of another teen’s poor performance?

Note: This idiom means to believe wrongly that someone or something has the same bad qualities as someone or something that is similar. It’s often used in the passive voice. To be tarred is literally to be blackened (since the substance tar is black), and figuratively to have your reputation blackened.