In March 2018, several media articles reported that the US police said people shouldn’t follow the advice in the memes.
On 21 March 2018, the Los Angeles Police Department tweeted about the meme: “That is false. Operators are trained to recognise voice inflection, odd conversations that would indicate a dangerous situation, among other things.”
Even if you’re in the US or Canada, ordering a pepperoni pizza when calling 911 won’t necessarily signal to the operator that you need help. – Eileen Jahn