If you use WhatsApp often, you may have seen this message recently:

“Messages you send to this chat and calls are now secured with end-to-end encryption. Tap for more info.”

This is useful, even if you’re not a techie. It means you will benefit from WhatsApp’s new security feature, an encryption it has put on all communication between you and your contacts. This ensures that no one else can access your messages by hacking WhatsApp or by intercepting your messages while they’re being sent. A hacker would have to get physical access to either your phone or the phone of the person you’re communicating with, which is a lot harder, making you a lot safer.

For the majority of WhatsApp users, nothing changes, except they will have the added comfort of knowing their conversations are more secure. WhatsApp may even get more users among people who were already looking for secure communications. The new feature makes WhatsApp more competitive with mobile apps that already had strong security implementations such as Telegram, a rival instant messenger.

What’s interesting about this new layer of security is the legal angle: this could have serious implications in law. Before this update, intelligence agencies (such as the United States’ FBI) and police forces could get hold of WhatsApp messages fairly easily. They say they’re doing this in the name of upholding the law, but an unfortunate side effect is that they’re undermining and in some cases violating the user’s privacy. That’s how information was retrieved from phones used by Vybz Kartel (Adidja Palmer) and his associates involved in the murder of Clive “Lizard” Williams.

With this WhatsApp update, the law will find it difficult to get access to people’s information. The encryption information is kept strictly between the participants in each WhatsApp group or individual chat. This move by Facebook (owner of WhatsApp) was encouraged, no doubt, by the recent dispute between Apple and the FBI over the San Bernardino shooter’s iPhone data. This is only the latest landmark on the long road of information security.

We have to find the balance between privacy and security. No one is saying the police shouldn’t be able to do their jobs, but at what cost? How much of our privacy are we willing to give up? Until we find an answer that everyone can agree on, there will continue to be an arms race between encryption and other data protection measures and law enforcement’s ability to crack them.