Cybercrime is a crime which is done using a computer and an internet connection to hack into someone else's account or a private/confidential website, without the knowledge of the account holders or the owners of a website, with an intention to steal information or taint the image of the persons concerned in any way.
Usually, those who commit cybercrimes are called hackers. These hackers deliberately hack an account or website, for various reasons like burglary, piracy of copyright content, child pornography, etc.
1. So according to the definition, yes accessing someone's Google account without their knowledge/permission is a Cyber Crime in India and other parts of the world too.
2. The punishment of Cybercrime usually ranges from six months to five years, depending on the type of cybercrime the hackers committed.
3. It is a very serious issue. No one is allowed to peek into others personal information. It is as confidential for the common public as for the government. And usually, cybercrimes affect a lot of lives, can leak very private information etc which may harm the person concerned and even the persons related to the person concerned.
If the person whose account has been hacked by your friend comes to know about it, he/she may easily file a complaint. It is similar to filing an FIR. Also, such FIRs can also be filed online now. Your friend may get into big trouble in this case. He/She shouldn't have done that.
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