Conversation so far:
What kind of impact did legalized abortion have on crime as argued by Steven Levitt?
Donohue and Steven Levitt argued that the legalization of abortion can account for almost half of the reduction in crime witnessed in the 1990s.
Did the legalization of abortion affect the crime rate in any other way besides reducing it by almost half?
In 2003, Theodore Joyce argued that legalized abortion had little impact on crime, contradicting Donohue and Steven Levitt's results.

Question: Who opposed the abortion movement?
Self-contained rewrite: Who opposed the impact of legalized abortion on crime argued by Steven Levitt?