Punishment absolutely works as deterrent. Boy I know people that would absolutely forge the tax declaration, if it wasn't a terrible fine if they do!
The key point is the probability of the punishment being enforced. There is a trade off calculation going on, like "I could get 5 years prison and 10 grand fine... IF they catch me!". Studies suggest, that if you have 100% probability of being caught, then the punishment is extremely good deterrent.
Surely this can’t be true - as a trivial example I would be surprised if removing parking fines wouldn’t increase parking violations, or if Singapore stopped punishing littering that it wouldn’t affect the amount of littering etc
Maybe the difference between a 10 year or 20 year sentence for murder doesn’t make much difference, but if murder had no punishment at all I would be very surprised if that wouldn’t raise the murder rate!
While I agree that people conducting corporate fraud think they will get away with it - I don't agree that the long sentences won't act as a deterrence. If you set the sentence for these sorts of crimes to 1 year rather than 15+, that completely changes the risk profile for people who think there is a 90% chance they will get away with it.
Sentence length has a small effect on crime rates, but what really matters is enforcement levels. If you have a 99% chance of getting caught & punished, you don't bother.
I think this just highlights how stupid the idea is that punishment doesn’t act as a deterrent
Your assertion is not the slam dunk you think it is.
There is no research I’m aware of on people for whom the prospect of punishment did act as a deterrent (i.e. people who decided not to commit the crime).
So I argue that there is a very big selection bias in literature surrounding the effectiveness of punishment as a deterrent .