From the Free Law Project:
We are happy to announce that we have compiled, collected and analyzed the complete collection of precedential federal tax opinions from the Board of Tax Appeals (1924-1942) and later the United States Tax Court (1942-). Our collection of tax cases spans two courts, nearly a century, and comprises nearly twenty-four thousand precedential opinions. We also have over twelve thousand non-precedential opinions in our database.
You can start reading and researching these opinions on Courtlistener’s Opinion Search, can browse decisions of the Board of Tax Appeals and the U.S. Tax Court by volume, and as always you can explore these cases via our APIs and Bulk Data.