JOEL BELZ Code of silence Why won't the IRS answer a basic question about tax law? By Joel Belz I STILL HAVE DOUBTS WHETHER THE NAME OF VERNICE B. Kuglin, who lives in Memphis, Tenn., will someday leap off the pages of America's history books along with those of Patrick Henry, Nathan Hale, and Rosa Parks. I do know that Ms. Kuglin must be a woman of some personal courage. Ms. Kuglin, a 58-year-old pilot for FedEx, made news a few days ago when a federal court jury found her not guilty on six charges of tax evasion and willful...