No; it's simpler than that. Tax fraud doesn't distribute by income; it distributes by nature of income, and the ease with which that income is validated. Some

No; it's simpler than that. Tax fraud doesn't distribute by income; it distributes by nature of income, and the ease with which that income is validated. Some really large proportion of Americans are basically W-2 filers taking the standard deduction. These Americans have no opportunity to evade taxes. Most income tax fraud probably takes place in the area of passthrough businesses and other areas where tax verification isn't simply a problem of reconciling what employer A (or brokerage B, for dividends and stock sales, or bank C, for interest) said they paid to person P with what person P reported on their return. TL;DR - it's hard to execute a fraud when the IRS already has the corresponding 1099s on-file for you.