What am I missing?

.@MichaelCohen212 just gave a revealing answer on why Trump won’t release his taxes: because he’ll face a massive bill for back taxes. Hadn’t thought of that. Could it be that simple?

— Jim Sciutto (@jimsciutto) September 16, 2020

How? If he filled them, they’ve already been processed by the IRS, so how would this work?

— Yeah Sure WTF Ever 🇨🇦🇺🇸❤️🇺🇸🇨🇦 (@YeahSureWhatev2) September 16, 2020