As election season ramps up, voters will be seeing a lot of campaign advertisements on television. Without exception, these ads will conclude with a disclaimer that the politician being endorsed has sanctioned the spot. Usually, the person will say or be quoted as saying “I approve this message.” It’s clearly a requirement, but why? And how did it get started?

The practice is a relatively new one. In 2002, the Bipartisan Campaign Reform Act was passed, along with the Stand By Your Ad provision. The Act, which was backed by then-senators John McCain and Russell D. Feingold, was intended to further legitimize campaign contributions by banning large corporate donations. Stand By Your Ad mandates that anyone running for federal office stamp “I approve this message” as part of their campaign commercials. The goal was to curb muckraking, where candidates would lob ceaseless insults and accusations at one another. With Stand By Your Ad, lawmakers were hoping political candidates would think twice before engaging in dirty tactics and then attempting to deny any involvement. Call it a self-imposed campaign shaming.

The Federal Election Commission (FEC) is very specific about how that disclaimer should appear. According to the FEC, the written statement must come at the end of the ad, appear for at least four seconds, be readable against a contrasting background, and occupy at least 4 percent of the vertical picture height. The candidate will typically identify themselves and say the message aloud.

If the message was not approved by a candidate, then the spot will typically name the entity that is responsible—a political committee, group, or person. There’s also usually language about who financed the commercial.

So does this “play nice” edict actually work? According to research from the Haas School of Business at the University of California, Berkeley and published in the Journal of Marketing Research in 2018, the answer is: Not really.

Negative campaign ads made up 29 percent of political persuasion spots in 2000, and that number rose to 64 percent in 2012. In the week before the 2016 presidential election, 92 percent of ads were characterized as negative.

One possible reason: By stamping a negative message with “I approve,” candidates might actually be perceived as more credible by voters, as they're showing that they are willing to stand behind what viewers infer to be truthful statements. In a study of 2000 people using both real and fictional ads, researchers found that “I approve this message” didn’t change their perception of positive ads or personal attack ads, but did increase their confidence in politicians using policy-based attack ads.

The appearance of federal regulation, even if there’s no actual regulatory approval over a statement, seems to give messages credibility. So long as a candidate “approves” a message, positive or negative, voters may perceive their subjective statements as the truth.

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