Prosecutor Juan Martinez’s feisty courtroom demeanor could put his case against admitted killer Jodi Arias in jeopardy.

If the jury perceives his aggressive questioning of Arias as unfair or inappropriate, it could make them sympathetic toward her.

During his first day of cross-examining Arias Thursday, Martinez raised his voice multiple times and cut her off when she didn’t answer his questions the way he wanted. Arias will return to the stand Monday to face more tough questions from Martinez.

Read more: Arias: I didn't want to reject him

In Session host Vinnie Politan is a former prosecutor, and he says the relationship prosecutor Jeff Ashton had with the jurors in the Casey Anthony trial may have played a role in how they reached a not guilty verdict.

“It’s always a danger, you know, because, you always want to bond with the jury. I don’t know how much bonding was done during the jury selection process but apparently after speaking with jurors, defense attorney Jose Baez did a much better job of schmoozing the jury than Jeff Ashton did. Juan Martinez is a bull in a China shop. We’ve seen him, he’s rough on every witness. You know, I always pick my fights at the appropriate time, you know. And then there’s other times you kind of ingratiate yourself to the jury,” said Politan.

Read more: Why do Arias' other boyfriends matter?

Politan says Martinez is a seasoned prosecutor, and his experience will keep him from going too far.

“Bottom line here is Juan Martinez has been doing this a long time. And he’s been doing it a long time in Maricopa County, Arizona. OK, so he knows the people of his community. Like if I’m arguing a case in South Carolina, it might not be the same way I argue a case in New Jersey. You have to know your audience. And I trust local prosecutors know their audience and how far they can go,” Politan said.