LONDON » England has long been a mecca for aggrieved people from around the world who want to sue for libel. Russian oligarchs, Saudi businessmen, multinational corporations, American celebrities — all have made their way to London's courts, where jurisdiction is easy to obtain and libel laws are heavily weighted in favor of complainants.

Embarrassed by London's reputation as “;a town called sue”; and by unusually stinging criticisms in American courts and legislatures, British lawmakers are seriously considering rewriting England's 19th-century libel laws. A member of the House of Lords is preparing a bill that would, among other things, require foreigners to demonstrate that they have suffered actual harm in England before they can sue here.

It is not only news organizations that are running afoul of the law. Environmentalists, anti-corruption campaigners, medical researchers and soccer fans posting criticisms of their teams on blogs have all been sued or threatened with legal action in recent years.

The justice secretary, Jack Straw, said recently that he was alarmed about “;libel tourism.”; And in the House of Commons, a committee has listened to a parade of witnesses denounce the current law as perverse, unfair, prohibitively expensive, contemptuous of free speech and an anachronism in an age when access to articles on foreign Web sites can be obtained anywhere.

“;We all have substantial and increasing concern at the potential of the English law of defamation to affect our work unjustly and oppressively,”; a consortium of foreign newspapers, publishers and human rights organizations, including The New York Times, said in a statement to the committee.

Noting that “;one 'hit' in England is enough for a multimillion-pound libel action in London,”; the statement called England's libel laws “;repugnant to U.S. constitutional principles”; and said that because of the threat of costly lawsuits, some American newspapers were considering abandoning distribution here and installing firewalls to block access to their Web sites in England.

More than 20,000 people, including Richard Dawkins, the evolutionary biologist, have signed a petition saying that the laws “;discourage argument and debate”; and have no place in scientific disputes.

“;It's quicker and easier and simpler to apologize and settle,”; said Simon Singh, the author of “;Fermat's Enigma,”; who, having refused to apologize or settle, is battling the British Chiropractic Association over an editorial he wrote for The Guardian accusing the group of promoting “;bogus treatments.”;

English libel law is the opposite of America's in many ways. In the United States, the plaintiff, or accuser, must prove that the statement in question was false; public officials must also prove that it was made maliciously, with “;reckless disregard”; for the truth. In England (Scotland has its own system), the burden of proof rests on the defendant, whose statements are presumed false and who must establish that they are true.

Despite the law, or even because of it, some British newspapers have a deserved reputation for irresponsible journalism.

“;We have a vicious, aggressive press here,”; Nigel Tait, a partner at Carter-Ruck, a law firm that often represents plaintiffs in libel suits, wrote recently. “;It's all great — until someone writes something false about you.”;

Because it can be expensive and traumatic to pursue a case, aggrieved parties like minor celebrities may be reluctant to sue. As a result, the scandal-sheet tabloids tend to focus on them rather than on the rich and powerful.

“;I have a friend who is the editor of a national newspaper whose board has said to him, 'Don't take on the oligarchs; we simply cannot afford it,”;' said John Kampfner, chief executive of Index on Censorship, which, along with English PEN, a group that promotes literature and human rights, recently produced a report on libel.

A number of states, including New York, have passed legislation making English libel rulings difficult to enforce in American courts. Congress is considering similar legislation.