Editor's note: Mel Robbins is a CNN commentator and founder of inspire52.com, providing daily "good news" stories and viral videos. She hosts "The Mel Robbins Show" Sundays from 7-9 p.m. on WSB 95.5 in Atlanta and News 96.5 in Orlando. In 2014, she was named Outstanding News Talk Radio Host by the Gracie Awards. The opinions expressed in this commentary are solely those of the author.
(CNN) -- Whoever is running the social media strategy for the New York Police Department needs to be fired because that person has no idea how to follow the rules of social media.
On Tuesday, the NYPD's Twitter account, @NYPDNews, asked New Yorkers to "tag themselves" in photos with New York Police officers using the hashtag #myNYPD. Before midnight, more than 70,000 tweets containing photos or stories of police brutality flooded the Twittersphere, replacing #HappyEarthDay as the trending topic by late Tuesday evening.
It was a disaster.
Instead of igniting a positive viral PR campaign, a single tweet managed to set the NYPD's reputation on fire. They should have seen this one coming. Twitter is a great tool to read breaking news, research prospective clients, connect with friends, discuss live events or gain access to your favorite celebrity. But it's a terrible place to try to control a conversation because you simply can't.
Social media disasters are becoming a regular occurrence. Remember the PR executive from media company IAC who sent out a racially offensive tweet and raised a firestorm? Or when Burger King's account got hacked and fake tweets referencing race and drugs were posted?
It's like rubbernecking an accident on the highway -- we can't help but stare and comment before we move on with our lives. And while #myNYPD will be largely forgotten by you and me, the NYPD will feel the pain for months to come.
Rule 1: Every social media platform has a very specific demographic
Facebook users are a different demographic than Twitter users, just as Pinterest users are different from Instagram users. Twitter users are the youngest demographic of all major social media outlets. If you tweet, you're speaking to 18- to 29-year-olds, not middle-aged moms on Pinterest and Facebook. And those millennials are unforgiving -- they care more about "social expression" than "social obedience," which means they'll tweet what they feel with no filter.
Rule 2: You will never control the conversation on Twitter
Tweets are like roaches; once you spot a contrarian or sarcastic reply, you know there are hundreds more right behind it, and there's no way to exterminate them. If you need to control the conversation, use Facebook. On Facebook, you can delete individual comments that do not contribute to your overall social goal. On Twitter, the users are in control.
Rule 3: Social media is often ruled by the haters
Social media is a love-hate world, and among your followers you'll have just as many fans as foes. Even Starbucks, one of the most dominant brands in the United States, is probably publicly hated more than it's praised.
The NYPD has a well-organized social media savvy hater: Occupy Wall Street NYC. And they jumped all over #myNYPD using the Occupy Wall Street NYC Twitter account. In fact, they are credited with making the photos of the police brutality start to trend nationally.
Rule 4: If you ask people on social media what they think ... they'll tell you
People on social media are ruthlessly honest, way more so than they would be in person. Ask their opinion about your brand and you'll get an instantaneous barometer (the good, the bad and the atrocious). Forget the user-generated PR campaign. It's better to monitor your reputation on Twitter using reputation management software and reply directly to people who tweet bad things about you.
Rule 5: The odds are not in your favor to get good news
Despite the overwhelming success of viral positive news websites like Upworthy or Inspire52 (disclaimer: I'm the founder), most content that gets shared online is negative, funny or sarcastic. And, unless you request that people tell you their positive experiences, research shows that humans are more likely to remember negative experiences. But obviously, there are exceptions, like NYPD's Twitter fiasco.
What's the moral of this story? If you want to use social media to promote a brand, either use the rules to pick the right platform and own the conversation or social media will own you.
NYPD should have solicited feel-good user generated photos through a contest on Facebook, Instagram and Pinterest and then published them on Facebook where they could delete the negative and sarcastic responses.
Now that you know the rules, answer this question: What do you think will happen if you invite the youngest and most urban demographic on Twitter (and Occupy Wall Street NYC who happens to follow you) to post photos of cops in New York City?
Unfortunately, common sense, safe driving and social media rules are a lot like deodorant, the people who need it the most don't use it.
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