tax dodge

(somewhat derogatory, informal) A scheme (legal or illegal) to avoid paying tax, or to pay less tax.

1927, United States Code Annotated:

[…]indication that taxpayer accepted public employment as a tax dodge, and where taxpayer earned approximately 98% of his income from his Oregon based business activities, taxpayer was a "public employee" and was therefore entitled to deduct[…]

1941, “PARK 'GIFT' TO CITY CALLED TAX DODGE”, in The New York Times:

[headline] PARK 'GIFT' TO CITY CALLED TAX DODGE