Dr. Ehrenfeld was a visiting scholar at the Columbia University Institute of War and Peace Studies, a research scholar at New York University School of Law, and a fellow at Johns Hopkins SAIS. Her Ph.D., in criminology, is from the Hebrew University School of Law.

Dr. Ehrenfeld's articles have appeared in The Wall Street Journal, The New York Times, Newsweek, The Guardian, The Washington Times, National Review, Huffington Post, the Eurobserver, The Jerusalem Post, the New York Sun, and the Los Angeles Times. She has appeared as a commentator on television and radio news programs, including The O'Reilly Factor, Fox News, CNN, American Broadcasting Company|ABC, NBC, and MSNBC. She is also a contributor to the Terror Finance Blog.

Dr. Ehrenfeld has testified before the U.S. Congress, the European Parliament, the French Parliament and the Canadian Parliament on terror financing. She has also provided evidence to the British Parliament alleging corruption of the Palestinian Authority, and has testified before the U.S. Congress on terrorism related issues.

Dr. Ehrenfeld became involved in an international legal controversy when she was sued for libel in the United Kingdom.

In her book, "Funding Evil", Dr. Ehrenfeld alleged that Saudi billionaire Khalid bin Mahfouz had financed al Qaeda through his bank and charitable organization. Mahfouz denied the allegations. Dr. Ehrenfeld, a U.S. citizen based in New York, had not written or marketed her book internationally and refused to acknowledge the jurisdiction of the British court over her case. Her refusal resulted in the British Court awarding a default judgment against her.

Represented by her attorney, Daniel Kornstein, Dr. Ehrenfeld pre-emptively countersued Mahfouz in New York to obtain a declaration that the judgment would not be enforced in the United States and that her book was not defamatory under United States defamation law. When the New York courts ruled that they lacked personal jurisdiction over Mahfouz, the New York State legislature took immediate action and unanimously passed the Libel Terrorism Protection Act (also known as "Rachel's Law"). Rachel's Law was signed into law on April-29-2008. The law "offers New Yorkers greater protection against libel judgments in countries whose laws are inconsistent with the freedom of speech granted by the United States Constitution." Governor Paterson Signs Legislation Protecting New Yorkers Against Infringement Of First Amendment Rights By Foreign Libel Judgments.

As of July 2010, six other states have passed analogs to Rachel's Law: Illinois, Florida, California, Tennessee, Maryland, and Utah. A federal bill based on Rachel's Law was pass unanimously out of the Judiciary Committee and will soon be considered by the U.S. Senate. The bill, S. 3518, the Securing and Protecting our Enduring and Established Constitutional Heritage Act (SPEECH Act), includes several measures aimed at closing loopholes in First Amendment protections for free speech. The act bars the enforcement of foreign libel judgments that do not meet with American standards of due process and First Amendment protections. The burden of proof is placed on the party suing for enforcement. The party suing to prevent enforcement may also sue the libel plaintiff for a declaration that the foreign libel judgment is "repugnant" to American constitutional law, and is entitled to attorney's fees for the legal proceedings.

Dr. Ehrenfeld's efforts at libel law reform in the United States have also led the British media to demand reform of their own libel laws. The British government has yet to act.