… is from page 93 of Michael Huemer’s superb 2013 book, The Problem of Political Authority (footnote deleted):
[T]he marginal social benefit of each dollar given to the government is much less than the marginal social benefit of a dollar given to any of a variety of extremely effective private charities. In this case it is not wrong to evade one’s taxes to send the money to charity; indeed, doing so is praiseworthy.