On September 9, 2021, the Tax Court issued a Memorandum Opinion in the case of Kaebel v. Commissioner (T.C. Memo. 2021-109). The primary issues presented in Kaebel v. Commissioner were (a) whether the petitioner was precluded from arguing that the IRS did not send him deficiency notices; (b) whether the IRS erred in certifying that the petitioner had seriously delinquent tax debt; and (c) whether the petitioner should be sanctioned for advancing the groundless argument that the IRS had not sent him deficiency notices. Summary of Kaebel v. Commissioner The IRS certified the petitioner under IRC § 7345 as an individual having a seriously delinquent tax debt. The petitioner challenges the certification as erroneous, arguing that, because the IRS failed to send him statutory notices of deficiency in tax for five of the six tax years underlying the IRS’s certification, he owes no tax for those years and his remaining tax…