The best-known "lettres de cachet", however, were penal, by which a subject was imprisoned without trial and without an opportunity of defense (after inquiry and due diligence by the "lieutenant de police") in a state prison or an ordinary jail, confinement in a convent or the General Hospital of Paris, transportation to the colonies, or expulsion to another part of the realm, or from the realm altogether. The "lettres" were mainly used against drunkards, troublemakers, prostitutes, squanderers of family fortune, or insane persons. The wealthy sometimes petitioned such "lettres" to dispose of inconvenient individuals, especially to prevent unequal marriages (nobles with commoners), or to prevent a scandal (the Lettre could prevent court cases that might otherwise dishonour a family).