During the course, I give various examples of choosing specific words and phrases to garner sympathy or empathy from the reader if it is warranted. Until recently, the efficacy of using pathos has been mostly based on anecdotal evidence that it will make a judge feel a certain way about a defendant or victim helping the attorney advocate for his or her client.
In December 2015, a new paper was released that looks at the use of emotional language in briefs before SCOTUS and analyzes the briefs and the ultimate outcome of the case.
From the abstract:
The legal brief is a primary vehicle by which lawyers seek to persuade appellate judges. Despite wide acceptance that briefs are important, empirical scholarship has yet to establish their influence on the Supreme Court or fully explore justices' preferences regarding them. We argue emotional language conveys a lack of credibility to justices and thereby diminishes the party's likelihood of garnering justices' votes. The data concur. Using an automated textual analysis program, we find that parties who employ less emotional language in their briefs are more likely to win a justice's vote, a result that holds even after controlling for other features correlated with success, such as case quality. These findings suggest advocates seeking to influence judges can enhance their credibility and attract justices' votes by employing measured, objective language.
Now we have empirical data that shows that the use of measured, objective language is best - at least in front of the SCOTUS Justices.