Why does telling Siri to charge your phone call the police? Look to India.
Earlier today The Verge pointed out that, if you use an iPhone to tell Siri, "Charge my phone to 100 percent," it will attempt to call emergency services (giving you a five-second grace period to cancel the call). This is true. DO NOT try it, as the police dislike being summoned to your home for no reason. Some have suggested that this behavior is a bug, while others guess that Apple has created a covert way to summon the authorities, should the caller be in a dangerous situation. That's clever, but I don't think that's what's going on.
First, it's likely that Siri is responding to the word "phone" followed by a number. Remember, "phone" can be a verb and a noun. For example, if you tell Siri, "Charge my phone to 50 percent," it will attempt to call the number 50. So why does 100 call emergency services? I believe it has to do with the emergency numbers stored on a SIM card.
SIM cards contain a list of pre-programmed emergency numbers. For example, most GSM mobile phones have 112, 999 and 911 always available [PDF]. Additionally, manufacturers can add country-specific emergency numbers, in case their customers want to travel. Which brings us to India.
India, unlike the US and EU countries, does not have a common emergency services number. Instead, these are the emergency numbers in the country:
Medical - 102, 1298, 108, 112
In the end, Siri is simply calling the number after "phone," and 100 happens to be an emergency number. It's kind of a boring answer, but there is is. Also, Siri can't initiate a charge anyway, so who would make this request in the first place?