Department of Justice just released an indictment of 12 aligned Russian spies paying for computers around the world with crypto this is how law enforcement is using the blockchain to track and arrest criminals. It would be better to use cash at this point for criminals as they flee Bitcoin.
Because the Blockchain is a public ledger anyone can view anyone’s transaction or balance. As long you know the bitcoin address or specific amount and date and all you need to do is look at the blockchain.info and search there wallet try 1HiMoMgBaAikFHgAt3M4YJtetp4HrnsiXu in the search field and you will see all there transaction.
This is one way another way would have your computer connect to the bitcoin network and this is called a node when it’s on the network this will allow you to see every transaction ever created from day 1.