In May, Transportation Security Administration screener Rolando Negrin pummeled a co-worker with his government-issued baton. The feud began, according to a Miami-Dade Police Department report, after Mr. Negrin's training session with one of the agency's whole-body imagers. The scan "revealed [Mr. Negrin] had a small penis," the disgruntled co-worker told police. After a few months, he "could not take the jokes any more and lost his mind."

Now the TSA is rolling out these ultra-revealing imagers across...