Illegal things to buy!!

[owm123]

Well as we all know that whenever we transact it always go through blockchain first. So is it possible that blockchain can detect illegal trasanction such as buying drugs, guns, hitman etc., especially on deepweb. And where does bitcoin go when blockchain detects a illegal transaction?

There are companies that do aim at detecting and monitoring illicit transactions in bitcoin for use by law enforcement, governments and merchants. For examples

https://www.elliptic.co/
http://www.coinalytics.co/
http://sabr.io/

An they can do this because bitcoin is not anonymous, but only pseduo-anonymous.

Wow I didn't even know that Bitcoin reconnaissance is even a thing until now. Elliptic are saying on their website that they can trace Bitcoin addresses of dark web entities wow can they really do that? I thought deals on the dark web are very hard to track down if not impossible. Maybe they have developed an algorithm to datamine suspicious transactions or something because if they are doing this manually it sounds crazy.

Thats exactly what they do, datamine blockchain + publicly available information + information from exchanges, law enforecements etc. Once they connect a single address of a user  with his/her real identity, they just follow the blockchain trial. Everything is in blokchain, as its public ledger.

[extrabyte]

Well as we all know that whenever we transact it always go through blockchain first. So is it possible that blockchain can detect illegal trasanction such as buying drugs, guns, hitman etc., especially on deepweb. And where does bitcoin go when blockchain detects a illegal transaction?

block chain don't know which transaction being done for an illegal purchase or deal. all transaction are same.. block chain can't detect transactions. but if we know an address of a scam person and report about it in blockchain, then may be blockchain can cancel transaction to this address.

[Oscoda]

Blockchain itself does not know what is payed with the transaction and that also would be stupid if you asked me.
Overall its possible because there is nothing different than with a normal payment compared with illegal things..

[Lokfar]

Well as we all know that whenever we transact it always go through blockchain first. So is it possible that blockchain can detect illegal trasanction such as buying drugs, guns, hitman etc., especially on deepweb. And where does bitcoin go when blockchain detects a illegal transaction?

block chain don't know which transaction being done for an illegal purchase or deal. all transaction are same.. block chain can't detect transactions. but if we know an address of a scam person and report about it in blockchain, then may be blockchain can cancel transaction to this address.

There are many illegal things that you can buy with Bitcoin and that would be nice but also dangerous, but you cant stop it and also not control it.
And if there will be more users that is going to use Bitcoin they will also get to know about the illegal things.

[bob123]

Why should Bitcoin "Start to check blockchain" for any activity?
Btc is just a currency.

Illegal activities should be checked by governments.

[romero121]

I think Blockchain is unable to detect that what thing is bought with the transaction occur, and I think it also does not detect that which person is that who send or receive that bitcoin transferred.

Exactly bitcoin as a transaction medium helps in transferring money to any one at any corner of the world. So it doesn't matter with the product. It depends on buyer and seller whether the product is is a legal or illegal thing.