Genie, you're more likely thinking of the US legislatures, and their capacity for generating farce seems endless. The poor IRS is only an enforcement dogsbody that dances to Congress's tune.

Gator, that has already been copiously addressed in other threads. Copyright covers non-generic arrangements generated from public domain material. However, the copyright only covers that arrangement or recording. No one must seek your permission to derive a different arrangement from the original work.

If your (for-profit) performance is identifiably cloned from someone else's copyrighted arrangement, you are infringing copyright, regardless of whether the original work is in the public domain.

[Same disclaimer as in my previous message.]