In the United States, such tactics violate the Fair Debt Collection Practices Act.

Gigi Gordon, a Santa Monica criminal-defense lawyer, said the prosecution's tactic had violated a trial lawyer's cardinal rule: Never elicit evidence whose outcome is unknown in advance.

Complicating the task of countering the manipulation, officials said, it appears that the tactic did not violate any specific election rules, only their general spirit.

A spokeswoman for Sharman Networks, the distributor of KaZaA, said that the tactic violated the company's user agreement, which prohibits making search requests to accumulate information about individual users.

The Government has assembled persuasive evidence that Microsoft's tactics violated prohibitions against using monopoly power in one area to crush the competition in others.

His tactics do not technically violate a suspect's rights, but they do stretch the legal definition of coercion.

Even as Sir Gordon was buying the stock, SCM's lawyers were drafting a lawsuit against Hanson, charging that his tactics had violated tender offer regulations.

The legality of these sort of tactics have been challenged in some jurisdictions, on the grounds that such tactics violate privacy rights and/or are intended to incite later reprisals against such individuals.

A spokesman at the general prosecutor's office said the investigation was focusing on MOST's security services, which reportedly number 2,000 employees, whose eavesdropping and surveillance tactics violated the law.

Mr. Kane of the F.T.C. said it was unclear whether the tactic used in this case violated any law.