The point of protest, at least in theory, is to inspire change, to get something done. Yet, when it comes to politics, protest often leads nowhere. And, according to some recent experiments that piggybacked on real demonstrations in Mexico City, protests might actually be counterproductive among onlookers who experience them firsthand.

Political protest has always been engrained in the fabric of the United States, but whether it actually works is surprisingly unclear. Yes, the Civil Rights Movement of the 1960s led to the Civil Rights Act, but protests against the Vietnam War had little impact. More recent studies of immigration rallies suggest that protests' effects on political attitudes are often mixed.

One might think that's because significant protest is less common these days in the U.S., but that doesn't appear to be the case, writes University of Pittsburgh political science graduate student Cassilde Schwartz in an email. "Major Latin American cities regularly have several protests a day, and yet it's often hard to see any actual effects," Schwartz writes. "Basically, I wondered if it was possible that protesters were somehow shooting themselves in the foot."

To find out, Schwartz and her team phoned up 1,202 Mexico City residents and told some of them about a protest related to the disappearance and apparent murder of 43 students in southern Mexico. She then asked how likely they'd be to vote, contact elected officials, and so on. Overall, the results were simple: Compared with a control group, people who heard about the protest wanted to get more involved, she reported last week at the American Political Science Association's annual meeting.

"But [a survey or news report] doesn't look anything like real protests, which are deliberately loud, conflictive, and logistically inconvenient for as many people as possible," Schwartz writes. "Protests are like performances, and you certainly wouldn't expect an audience to have the same reaction while reading a summary of a film as they would if they actually saw the film."

So Schwartz devised a novel plan: Working with local activist organizations, she invited survey participants to interviews that, unbeknownst to them, had been timed and located to correspond with protests related to the disappearances. Eighty-eight people showed up for the interviews, but this time, the 69 that were thrust into a real-world demonstration reported they'd be less likely to talk about the issues, and even less likely to vote, compared to a control group of 19 people.

That, Schwartz writes, suggests some protests could be counterproductive in the long run. While, say, disrupting traffic could attract media attention, it could also lead potential supporters to shy away from getting involved, perhaps because seeing a protest in person triggers different emotions than hearing about it on the news might. "[I]t's actually a very difficult balance to make because the protests that tend to attract the media are often the most disruptive," Schwartz writes. "This could explain why it can be so difficult for protesters to maintain public engagement long enough for change to take place."

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