I sent a mail to a government agency for whistleblowing against aa institute, I was using protonmail as well as proton vpn. Can the mail be traced back to me(even my city) even with a court order or by the government agencies??(Because corrupt government and courts in India). I am afraid of retaliation from the institute and really stressed.
SMTP headers show the originating server and every hop to the destination. The headers also show the sender, plus that info is in the message envelope itself. Presumably you setup a free Proton Mail account for this purpose, so that would only reveal the message came from whatever name you supplied to setup Proton.
If India convinces Switzerland that you’ve broken some Swiss law, Proton could be forced to provide account details you provided when you signed-up and, if it was logged, the IP address from which you connected when you signed up and when you sent the email. While Proton VPN does not log traffic, I don’t know if that also applies to account sign-ups or connections to Proton Mail. However, if you signed-up for Proton from an Internet cafe or public WiFi that doesn’t require showing identification, then any possible IP address collected wouldn’t reveal your identity, but could reveal the city from which you connected.
Proton has a no logs policy on VPN. So IF Proton Mail does log connections, it would only show the the VPN IP, not your personal IP. Even better, though, would be anonymously using a public WiFi or Internet Cafe in a different city for all steps.
So a number of things would need to align on top of the seriousness of your accusation, the level of corruption involved, and the very unlikely change that anything you’ve done would be considered a serious-enough violation of Swiss law worthy of issuing a court order to Proton.
It is technically possible, but before they even attempt to trace it, they’ll have to go through the Swiss court first, because in Switzerland, it is forbidden to reapond to foreign agency demands without their explicit approval.
If swiss govt decides to rat you out, proton will be forced to give out your info…i.e., IP address. Nothing more. Because proton doesn’t collect a lot of data unlike google, they don’t have much to give out. And if you are balls deep in the govt’s ass, and asking this question, your are doomed. You must’ve heard about the recent pegasus attack on opposition and journalists (imagine being so incompetent, that u get caught by apple’s automated security, even with pegasus in your hands 
, fking losers unpadh gawar BJ party)
Btw, sign up using some other ip than ur, use proton onion site. (+ simplelogin alias maybe) they ain’t got shit on you.