Upvoted. Some more details FWIW:

> Telegram group chats are very much available to law enforcement if they can convince Telegram to hand over the data.

Telegram public channels and groups are open, including for law enforcement. They also say openly that they cooperate with everyone to take down certain illegal material from channels and open groups.

Telegram claimed as late as a few months ago - and nobody has proven otherwise in any form as far as I can see - that not a byte of their users private data (i.e. not on open groups or channels) have been handed over to any government.

I cannot prove this and also I'm getting more careful with Telegram these days (this might come as a surprise for some of you who know my history of defending Telegram) but I still think

1. if it was possibly to prove something else there are enough Telegram haters just on HN to make sure to leak it

2. just to be clear I still think it is a very good alternative for friend-to-friend-communication, group communication etc, I'm just looking for alternatives as I go forward, and also I am worried when I see police using it at work.

Don't get me wrong, I use Telegram every day despite their flaws. Their data security guarantees may be terrible, but their user experience is still outstanding. It's a testament to how good a chat ecosystem can be if you don't rely on Electron.

I have no reason to distrust the Telegram team, but the data model is simply not designed to keep messages secret. It's Telegram's biggest shortcoming, in my opinion. Things like channels don't need encryption, but group chats can use some WhatsApp-style crypto.

WhatsApp's UX (basically: trust all E2E keys, and show a little notification if the keys changed) makes E2E available to the common smartphone user without the hassle of say Matrix's manual verification. For those with a more security-oriented mindset, there's always the ability to show encryption status changes so you could investigate.

I'll probably be using Telegram for a few years despite its shortcomings. It feels a bit iffy to talk about sensitive personal matters through Telegram, but I know it'll be a while before I can convince any large group of friends to move to something more secure.

For now I'm bridging my Telegram accounts through Matrix, so it's not like I'd benefit much from the added security anyway.

> They also say openly that they cooperate with everyone to take down certain illegal material from channels and open groups.

Can you provide a link for that? I could only find that they'd hand over your personal account info if they get a court order claiming that you're a terror suspect (from https://telegram.org/privacy):

> 8.3. Law Enforcement Authorities

> If Telegram receives a court order that confirms you're a terror suspect, we may disclose your IP address and phone number to the relevant authorities. So far, this has never happened. When it does, we will include it in a semiannual transparency report published at: https://t.me/transparency.

> Can you provide a link for that? I could only find that they'd hand over your personal account info if they get a court order claiming that you're a terror suspect (from https://telegram.org/privacy):

Maybe I can:

First a note: "your personal account info" while somewhat correct makes it sound broader than what the paragraph below says: "your IP address and phone number".

That said, here is one that that at least partially confirms this:

From https://money.cnn.com/2015/11/18/technology/telegram-isis-sh... :

> "Our mission is to provide a secure means of communication that works everywhere on the planet. In order to do that...we have to process legitimate requests to take down illegal public content (sticker sets, bots, and channels) within the app."

(emphasis mine)

There seems to be more in the search results here (if you have access to kagi, if not apply now:)

https://kagi.com/search?q=telegram+takes+down+isis+groups+

Edit: here's another link from the first page of results in kagi: https://www.forbes.com/sites/parmyolson/2015/11/19/telegram-...

Another after I added "cooperate" to my query: https://www.europol.europa.eu/media-press/newsroom/news/euro...

As I recall, even one on one chats are not e2e encrypted unless you explicitly start a "secret chat". Please correct me if I'm mistaken.

You're right! Despite their weird custom protocol, their E2E chats are still considered completely safe to use.

In my experience, though, very few people use E2E chats, even in direct chats.

As someone who regularly defend Telegram against all kinds of nonsense: you got it exactly right : )

>if they can convince Telegram to hand over the data.

Or if they hack Telegram's servers. Or ask some other agency like the NSA (that hacks systems all the time) to do that for them.

As for the legal aspects, I'm fairly sure Telegram can be made to comply, no individual user's is worth losing (tens/hundreds of) millions of customers in that particular country. It's not like Telegram can't do that technically*, the server-side database encryption key is by definition in the RAM of the server system.

* That hasn't prevented them from actively misleading customers with their split-key-and store-parts-under-multiple-jurisdictions -scheme.

> Or if they hack Telegram's servers

Or they join the group chat

Sure, that works for public groups but generally the private group chats with sensitive private information about peoples' personal/business life are not public.

I’m curious how you think the US law enforcement agencies would compel Telegram to comply.

Why are group chats more exposed?

Encrypting messages for one person to read is relatively simple. Encrypting a message so that it can be read by multiple parties requires either sending multiple messages or agreeing a stable shared secret for the group chat. If you want to add/drop people from group seamlessly, while keeping everything encrypted, your app or your users will have to jump through lots of hoops. Most don't make the effort.

It's also the case doing that securely required pushing the boundaries of modern cryptographic protocols. Telegram's protocol graphs are novices' doodles compared to Signal's group encryption stuff formally described here: https://signal.org/blog/pdfs/signal_private_group_system.pdf

On the other hand Signal has made a lot of questionable choices (such as adding a crypto payment that was just a money grab) that it has made me lost trust in the team and their motives. I no longer trust their build images and even if you build your own you have no idea what software the person you're talking to is running.

Sure, you do you. Personally I haven't seen anyone in e.g. the major infosec expert bubble abandon Signal for introducing mobilecoin. It's an opt-in feature, it doesn't make the message side security code harder to audit, and it's not like Moxie isn't painstakingly engineering everything to be secure from the get-go. I haven't once been disappointed in a new feature. OTOH consider Telegram that adds group video calls that nobody asked for: is it E2EE? Nope. Another security disparity to make explaining and understanding its security even more nightmarish.

Doesn't matter if signal is secure if nobody uses it. None of my friends are willing to use it because of the lack of features and horrible ui/ux.

The surface area for trust is expanded significantly.

Here in Puerto Rico we made our governor quit over exposed chat logs from a Telegram group. Encryption wouldn’t have saved it: someone took screenshots and leaked them to press.

In the new update, group admins can prevent forwarding and screenshotting. Unless the devices are "rooted"

There’s always going to be a degree of trust. Just take a picture of the chat with another phone.