What is the cheap trick Petrocelli uses during the trail according to obrien?

In the trial, Petrocelli employs the cheap trick of manipulating the jury's emotions by focusing on the defendant's background and circumstances rather than the facts of the case. O'Brien points out that this tactic distracts from the evidence and shifts the narrative in a way that can sway the jury's perception. This strategy is intended to paint the defendant in a negative light, appealing to the jurors' biases rather than their sense of justice.