How can proponents of a more equitable distribution of income use the law of diminishing marginal utility

Question:

How can proponents of a more equitable of income use the law of diminishing marginal utility of money to justify their position?
Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...