From Roger I. Roots, “When Laws Backfire: Unintended Consequences of Public Policy,” American Behavioral Scientist, Vol. 47 No. 11, July 2004, page 1382:
The unintended costs of welfare spending have rarely been compiled by academics. But research has shown that a substantial number of welfare recipients simply live in poverty by choice because of the attractiveness of welfare programs. During the mid-1980s, at least 5.7 million people—roughly one sixth of the population in poverty—were living in poverty by choice due to welfare (Goodman 1987). Each additional $1 million in welfare spending increased the poverty population by 250,000 people (Goodman 1987). Controlled experiments by the U.S. Department of Health and Human Serviced found that compared with similarly situated families not on welfare, families drawing welfare payments changed their behavior substantially.
The number of hours worked by husbands dropped 9 percent; by wives, 20 percent; by young male adults, an incredible 43 percent. The length of unemployment among husbands increased 27 percent; among wives it increased 42 percent, and for single female household heads it increased 60 percent. Divorce increased 36 percent among whites and 42 percent among blacks. (Goodman, 1987, p. 37).