The federal income tax filing deadline is not for a few months, so dealing with the IRS may not be at the forefront for you in January, but your actions between now and then could subject you to civil or criminal penalties.
This is because there may be a difference between what the average person considers willful and intentional conduct and genuine ignorance and neglect. Like the standard applied to business owners, the IRS is likely review how individual tax payers developed knowledge of the forms and disclosures necessary to properly document income, as well as whether they "should have known" about these perimeters.
Essentially, what may be innocent or even stupid mistakes to a taxpayer, the IRS may view them as calculated steps to avoid paying taxes or paying too little in that regard. For instance, if a taxpayer relied on cash deposits for the majority of his or her income and their lifestyle (i.e. purchases and payments on assets) did not reflect what was reported on their return, this could be viewed as an attempt to avoid paying the correct amount in taxes.
This is why a skilled tax law attorney can help when the IRS makes assumptions about you. Like any other prosecutor, the IRS must prove their case and not simply rely on what they may believe is willful conduct. An experienced lawyer can help in distinguishing what a taxpayer should know and what is not necessarily required knowledge in explaining how mistakes would have been made.
If you have questions about IRS inquiries and potential tax evasion or fraud charges, an experienced attorney can help.