Advocacy speeches should either argue one particular side of a controversial issue or urge listeners to take a particular action. While advocacy speeches can be about anything, popular subjects are usually in the fields of health, law and drugs.
One good speech idea that combines both health and law is whether physician-assisted suicide should be legal or not. Another intersection topic is whether those addicted to drugs should be placed in hospitals for specific medical treatment rather than thrown in prison as a punitive measure. A good health topic is whether electroshock treatment is an effective and humane treatment for patients.
A good legal advocacy topic is whether armed militias should be closely monitored by the Federal Bureau of Investigation or not. A similar topic is whether someone purchasing a firearm should have to register with the government at the time of purchase. Another popular legal topic is whether the death penalty should be abolished entirely or, if not abolished, whether it should be possible to punish certain juvenile offenders with it.
A solid health speech topic is whether heroin should be used to treat terminally ill patients for the pain they are in. A final health topic is whether all Americans should receive medical care regardless of their income via a national medical insurance initiative.