They should use full-anonymous coins such as Monero with secure connection and use decentralized exhange to hide their asset well
Also, the government can use 3rd party tracker such chainalysis to track down the coins and notify to all legal bitcoin services/exchange to notify government once the tainted coins is deposited to their services/exchange.
Correct! I was about to say the same thing. Converting money in to bitcoin through a centralized exchange will not help them to hide the dirty money trail and it will be easier for the government to catch them quickly. But anonymous currency like xmr or deeponion will be an ideal choice. Also while coverting they should make a cash deal instead of using any bank account. This way the trail can be hidden, otherwise, everything will become public.
If it is easy to catch them, then why is it that there are still corrupt government officials as of today? They must have caught a long time ago if it is easy right? That means that they are smart enough to outsmart everything just to hide their money. They have so many ways just to hide it. If they can't catch it from the banks how come they can catch them from crypto wallets that has so many ways to hide money? One thing is they can create many accounts and spread all their assets. Besides no one knows that it is a corrupted money yet. So it will be really difficult to catch, it is never easy. As you may know, some of the police or higher ups are puppets of corrupt officials. I just hope that this won't happen because it will be a bad thing for every country.