Following up on what @OneMoreFarang said, I had a Thai employee many years ago whose grandfather was murdered.
When the family complained that no action was being taken, it was suggested that 100,000 THB might "expedite" matters.
The boys knew the family had lots of money. That should help you with understanding the point being made above.
There are times, and I have personally experienced a couple. where you will interact with above board officers who
do their job professionally. Sadly, this seems to be the exception.
The forum is littered with stories of the woes experienced by those who were careless in this regard.