Within a short time of the announcement of the successful cloning of Dolly, politicians around the world either instituted or proposed bans on attempts at cloning humans. Then President Clinton issued a moratorium on the federal funding of experiments for human cloning, and several states issued complete bans on the research. In August 2001, the United State House of Representatives voted to ban human cloning. Japan has passed a law providing for a 10-year prison term for anyone found attempting to clone humans. Human cloning experiments have been declared illegal in the United Kingdom, although like the U.S., the U.K. has established a bioethics committee to study the broader issue.

Lawmakers in the various nations have raised varied objections. Some offer religious or moral concerns based on such issues as:

Taking reproduction out of the arena of marriage and putting it into the laboratory.
The number of unsuccessful animal cloning attempts that result in the production of non-viable or defective embryos, with the euthanasia or "natural" death of those embryos. Some religions define human life as beginning at conception, and some religious and ethical leaders define cloned fetuses as fully human and their destruction as immoral.
The fear that unscrupulous people could try to clone a new "master race."

The reasons for controversy are many. Some object to cloning from religious standpoints, considering the practice a form of "playing God." A great many early animal clones have been unsuccessful, born with severe birth defects. These animals' clones are euthanized, but that option would clearly be unavailable to human parents of severely malformed clones.