Opinion | The jury is studying Trump. These folks are studying Trump's jury.

You may not have heard of jury consultant Jo-Ellan Dimitrius, but there’s a good chance you’ve heard of one of her many clients, including O.J. Simpson and Scott Peterson and Kyle Rittenhouse. She worked alongside the criminal defense teams as Simpson and Peterson, respectively, stood trial on charges of murdering his ex-wife and his wife and with Rittenhouse’s team as he stood trial on charges that he wrongly killed two men at a protest that followed the police killing of a suspect.

Dimitrius became famous for developing the jury profile in Simpson’s 1995 trial. She described the “perfect juror” for the defense in that case as a “female, African-American with a high school education or less,” and her guidance helped Simpson’s defense team select specific individuals from the jury pool, including six African American women, to hear the case. Simpson, who died this month of cancer, was acquitted.

Last week, all eyes were on the jury selection process for former President Donald Trump’s New York trial on 34 Class E felony counts of first-degree falsification of business records. According to Dimitrius, who spoke to NBC News about the work jury consultants do, Trump’s team has been working with Magna Legal Services, a jury consulting company based in Philadelphia.

In addition to scrutinizing the jurors’ answers and body language, Magna — a firm Trump used in the second of two defamation trials writer E. Jean Carroll brought against him — would have been providing feedback in real time about their responses, as well as providing detailed research about them as the questioning process was ongoing.

We haven’t seen a jury consultant seated at the prosecution’s table, thus far, but it’s reasonable to suspect that it, too, might have consultants with whom it’s closely working. Jury consultants can be pricey, especially if they’re engaged to participate from jury selection to verdict. The district attorney’s office may not typically be able to afford the cost of a jury consulting firm but might make an investment in a case like this one.

Dimitrius’ storied career, including her recent work with Rittenhouse, provides some useful information and context for how such consultants might have worked to develop the “perfect juror” in this case.

Dimitrius began working “hand in hand” with Rittenhouse’s lawyers months before his trial in Kenosha, Wisconsin. Among other things, she conducted three different mock juries and ran various scenarios by them, including one in which Rittenhouse testified in his own defense. He ended up taking the stand and was acquitted.

Dimitrius calls the process of doing a deep dive into a juror’s background a “juror polygraph.” Consultants, who are sometimes lawyers but can also have backgrounds in psychology, criminology and sociology, are looking for inconsistencies, lies and falsehoods and finding evidence they can provide to their clients that a juror has a bias or prejudice against them that they should use to challenge that juror’s being seated.

Take what happened last week. On Tuesday, Trump’s legal team told the court it had concerns about specific prospective jurors who had answered the initial round of the 42 questions on the juror questionnaire. A woman was brought into the courtroom to answer to the defense’s allegation that Facebook posts she made in 2020 proved her bias against Trump. Based on her answers, Judge Juan Merchan ruled that she could be fair and impartial, and he denied Trump’s for-cause challenge, which is when jurors can be excused from serving because they can’t be fair and impartial. The judge did agree with the Trump team that a 2017 Facebook post from one man should disqualify him from the jury. He disagreed when the defense tried to strike a woman based on a social media post her husband had made in 2016.

Oftentimes you don’t ever see or hear from jury consultants. But they have outsized presences on legal teams because the front-line lawyers are heavily deferring to their insight and advice. A jury consultant doesn’t guarantee success, however. Simpson and Rittenhouse were acquitted, but Peterson was found guilty (of the first-degree murder of his pregnant wife and the second-degree murder of his unborn child), and a jury ruled that Trump owed Carroll $83.3 million.

The more information litigants have about a prospective juror, the better their chances to secure the right juries for their cases. As we saw last week in this Trump trial, jury selection is more about deselection than selection. With the retention and help of a skilled jury consultant, a defendant can wield more power and control than the prosecution during voir dire because he or she knows more about the jurors than what they provided in their answers to juror questionnaires or in their responses to both sides’ lawyers.

This article was originally published on MSNBC.com