Pennsylvania State University head football coach Joe Paterno watches his team during practice on November 9th, 2011, in State College, Pennsylvania. (Photo: Rob Carr/Getty Images)

Changing people's minds on emotionally charged issues is an enormous challenge. But new research reveals a technique that is more effective than most: You just need to lay out the facts—while exerting intense peer pressure.

"While information plays a role in changing a person's opinion, the social delivery of that information has the greatest effect," write Daniel Mallinson and Peter Hatemi of Pennsylvania State University. "Humans have a demonstrated proclivity to conform to their peers when faced with social pressure."

The study, published in the journal PLoS One, examined reactions to the 2011 firing of Joe Paterno, head coach of the football program at Penn State. The decision to sack the legendary coach in light of child sexual abuse charges against one of his top assistants, Jerry Sandusky, "invoked strong and diametrically opposed opinions" in the university community, the researchers note.

The question was still being hotly debated on campus in 2013, when the researchers conducted their study. Their research featured 58 people, almost all Penn State undergraduates. All began by offering their opinions on five campus issues, including Paterno's firing.

Thirty-four of the participants then participated in separate "discussion sessions," in which they were paired with two to four research assistants. After reading an information sheet that provided a refresher about the Paterno controversy, and presented common arguments and counter-arguments regarding his firing, the participant was asked whether they felt the firing was appropriate. The others then took the opposite side, and the discussion commenced.

After about 30 minutes of back-and-forth, the participant filled out an anonymous ballot with his or her "final opinion." The researchers took note of whether that viewpoint had shifted due to the discussion.

Another 24 participants also read the fact sheet and summary of the arguments, but did not engage in discussion. They, too, then offered their final opinion.

The researchers report only 8 percent of the people in the latter group shifted their stance. But among those who took part in a discussion where they were outnumbered, that number rose to 38 percent.

"Social pressure and/or the personal delivery of information, as opposed to simple exposure to new information, had a profound influence on either true opinion change ... or conformity through public compliance," they conclude.

In debriefing sessions following the discussions, 47 percent of participants who took part in the debates said "they felt pressured or intimidated. Twenty-nine percent also freely said that they felt like they had to dig in and defend their position during the discussion. This included six people that ultimately changed their minds."

Analyzing videotapes of the sessions, and noting any differences between the participants' spoken opinions and written decision, provided more nuance. "Most individuals that changed their opinion did so out of a combination of (new information and social pressure)," the researchers write.

"But there were people who only changed their opinion overtly, in order to gain social acceptance, as well as those who did not want to give the appearance of changing their mind, but still wanted to be right."

"While we identify individuals whose behavior was prompted by either social pressure or information," they add, "the largest group responded to a combination of the two."

So if there is an outlier in your group of close friends that plans to vote for the other party, don't sit down with them one-on-one. Gather some information, get together a small group, and get to work.

It may not be the most graceful or ennobling way to change minds, but being in the minority is almost always uncomfortable. Placing someone in that position can lead them to see things in a new light.