I don't need to defend the tax code. Every time it is "simplified", it tends to get more complex. But since most returns are based on W-2 income, and the standard deduction has been increased substantially, it is difficult to see how many of them are incorrect. When one gets into hedging and most trades, yes, there are many ways of making a mistake.
But the code certainly recognizes the distinction between civil and criminal activities. One must have the intention of committing fraud to be handed over to the criminal statutes. Purposely omitting substantial income, or fraudulently reporting income or other items are criminal offenses.
Well, I'll give you points for brains for admitting that you can't. But, in practice, aren't you doing so anyway?