In the United States v. Clark, Guardian case of 1979, the Supreme Court ruled on a tax dispute involving trusts established by Mr. and Mrs. Clifford F. Clark for their children's benefit in 1935 and 1946 respectively. The Clarks had retained significant control over these trusts which led to them being taxed as grantors under Section 677(a) of the Internal Revenue Code (IRC). However, after Mr.Clark’s death in 1969, his wife became guardian of her incompetent husband's estate but did not exercise any powers over it until her own death in 1972 when she was succeeded by respondent bank as guardian. The issue before the court was whether Mrs.Clark should be considered a "grantor" under IRC §677(a), thus making income from trust taxable to her estate or if it should be attributed to respondent bank instead since they were acting as guardians at time taxes were due. The Supreme Court held that despite having legal title and administrative duties regarding property during incompetency period, Mrs.Clark didn't possess requisite degree of control necessary for taxation purposes because she never exercised those powers while alive nor did she have power to revest assets back into herself upon regaining competency. Therefore,the income from trust wasn’t taxable against her estate but rather attributable to respondent bank who took up guardianship role post-death.

In the dissenting opinion for United States v. Clark, Guardian (1979), Justice Brennan disagreed with the majority's interpretation of Section 2053(c) of the Internal Revenue Code. He argued that this section does not limit deductions to only those expenses that are paid out during probate administration but also includes any other administrative expense allowable by law. According to him, Congress intended a broader reading of "administration expenses" and did not intend to restrict it solely to probate proceedings. Furthermore, he contended that limiting such deductions would create an inequitable tax burden on estates which take longer time in administration due to complex legal issues or disputes among beneficiaries. This could discourage executors from pursuing valid claims on behalf of an estate if doing so might extend beyond the period allowed for deductibility under IRS regulations as interpreted by majority view.