What do the Senate hearings on offshore profit shifting and a Supreme Court case decided on May 20, 2013 have in common? They both are generated by our system of taxing U.S. companies on their worldwide income, and they both are the result of the companies meeting their obligations to their shareholders, which is to legally minimize the amount of taxes they pay.

In the Senate hearings, Apple bore the brunt of the outrage expressed by Senators Carl Levin, D-Mich., and John McCain, R-Ariz., who demanded to know why Apple didn’t pay more in taxes. (It paid over $6 billion in taxes last year). The issue for the senators was the fact that, largely through the use of offshore entities, Apple escaped paying tax on some $30 billion in net profits over four years.

“It is unacceptable that corporations like Apple are able to exploit tax loopholes to avoid paying billions in taxes,” McCain said, characterizing Apple as “the most egregious offender” in employing such strategies.

But wait a minute—doesn’t “offender” imply wrongdoing? If Apple failed to reduce its taxes to the legal minimum, wouldn’t it be guilty of wrongdoing to its shareholders and the public who purchase its products (and who would be stuck with any price increases generated by the company voluntarily paying more than it was required)? As Apple chief executive Tim Cook said, “I can tell you unequivocally that Apple does not funnel its domestic profits overseas. We don’t do that. We pay taxes on all the products we sell in the U.S., and we pay every dollar that we owe.”

In the Supreme Court case, PPL Corporation was allowed to use a one-time U.K. windfall tax paid by its subsidiary as a credit against its U.S. tax liability (see Supreme Court Says U.K. Windfall tax Creditable). The case hinged on whether or not the tax paid to the U.K. had a predominant character as an income tax in the U.S. sense. In reversing the Third Circuit, the Supreme Court concluded that yes, it was an income tax in the U.S. sense, and therefore was creditable against U.S. tax liability.

Given the fact that both the Tax Court and the Supreme Court sided with PPL, while the IRS and the Third Circuit thought otherwise, there was room in the interpretation of the law for honest differences. It is akin to dynamic tension in the tax law. (For those who are old enough to remember Charles Atlas, he envisioned “dynamic tension” as a fitness routine—pitting muscle against muscle to build more muscle. It works best when the two muscle groups are of nearly equal strength).

Alas, the metaphor is not complete regarding the Senate hearing on overseas profits. While there may have been tension in the hearings, it was largely static rather than dynamic. But the two cases do serve to illustrate two companies attempting to minimize their tax within the confines of a worldwide system of taxation.