Legal restrictions on executive branch agency use of funds for public relations activities and propaganda can be found in statutory law, appropriations law, and federal regulations. Nevertheless, executive agencies frequently expend public funds to promote aggressively the agendas of presidents. The legal restraints against propaganda have proven ineffective for three reasons: first, agencies do not track spending on public relations activities, which makes congressional oversight difficult; second, the line between appropriate public relations activities and propaganda is blurry; and, third, enforcement of the laws against propaganda runs headlong into the separation of powers.