Jordan Thomas is chairman of the whistle-blower representation practice at Labaton Sucharow and was a former assistant director in the enforcement division of the Securities and Exchange Commission. Tom Devine is legal director of the Government Accountability Project and co-author of “The Corporate Whistleblower’s Survival Guide: A Handbook for Committing the Truth.”

Welcome to Wall Street, where the unwritten rule has always been that you don’t talk about illegal or unethical activities with law enforcement or regulatory authorities. Of course, this type of code of silence is not new. What is new is that this corporate omerta is being enforced by lawyers wielding gag orders.

In the wake of the economic crisis, our country debated how to break the cycle of corporate scandals that have plagued financial markets. Our financial watchdogs landed on two simple, fundamental truths: the investor protection status quo wasn’t working; and those responsible for law enforcement could not effectively and efficiently police the marketplace without help from private individuals.

Consequently, four years ago this Monday, the Dodd-Frank financial overhaul was signed into law. Among its many provisions, the statute established the Securities and Exchange Commission’s whistle-blower program, which offers eligible whistle-blowers significant employment protections, monetary awards and the ability to report possible securities violations anonymously. Potential monetary awards can be substantial because the agency secures over $3 billion a year in monetary sanctions and whistle-blowers are entitled to 10 to 30 percent of the sanctions collected as a result of their tips.

Although public debate on Dodd-Frank continues, few have questioned the whistle-blower program’s early success and potential to protect investors. The $8.9 billion settlement with BNP Paribas, although not reported through the S.E.C. program, is the latest example of how whistle-blowers can help law enforcement detect, investigate and prosecute corporate wrongdoing.

Mary Jo White, the S.E.C. chairwoman, said last year that the program “has rapidly become a tremendously effective force-multiplier, generating high quality tips and, in some cases, virtual blueprints laying out an entire enterprise, directing us to the heart of an alleged fraud.”

As Dodd-Frank has steadily increased the probability of detection, companies have become more sophisticated and aggressive in their efforts to discourage employees from reporting possible violations to the S.E.C. and other authorities. The legal countermeasures being deployed include a variety of employment, severance and settlement agreements that weaken both new and existing whistle-blower programs.

It was no isolated aberration that KBR, one of the nation’s largest government contractors, required employees seeking to report fraud to sign internal confidentiality agreements prohibiting them from reporting violations to law enforcement authorities. Rather, it reflects a growing trend of companies trying to silence whistle-blowers, at the same time Congress strengthens their rights.

Examples include: failing to educate employees about the S.E.C. whistle-blower program and their rights, unlike other corporate, state and federal programs; preventing employees from consulting legal counsel through the use of nondisclosure agreements, effectively eliminating their ability to file anonymously in accordance with S.E.C. rules; exploiting corporate whistle-blowers’ fear of retaliation and blacklisting by requiring notice of external reporting, in violation of their right under Dodd-Frank and S.E.C. rules to report anonymously; de-incentivizing tips by making employees sign agreements waiving any future monetary awards for blowing the whistle; and intimidating potential whistle-blowers with lawsuits to enforce secrecy agreements, a battle few whistle-blower have the desire and resources to fight.

To be sure, the vast majority of companies want to do the right thing. Many need guidance on lawful boundaries for standard employment agreements. Others appear to be intentionally crossing the line and using gag orders to chill external reporting. While no court has issued an opinion on the legality of these agreements in light of Dodd-Frank, many of them are clearly at odds with public policy, not justified by a legitimate corporate interest and inconsistent with principles of employment, contract and securities law. Because of the systemic nature and continuing harm, we have just filed a petition with the S.E.C. that will provide companies clear direction regarding these troubling agreements.

We are joined by a broad and growing coalition, representing more than 250 organizations and nearly two million citizens, including Americans for Financial Reform, the National Employment Lawyers Association, the International Brotherhood of Teamsters and other prominent groups. This coalition has also submitted a petition, urging the S.E.C. to hold a series of hearings around the country to discuss the problem of workplace retaliation and explore new ways to increase reporting, internally and externally. It also asks the agency to create an advisory committee on whistle-blower reporting and protection to recommend program improvements and best practices; and engage in appropriate rule-making to clarify and strengthen whistle-blower protections.

With whistle-blowers beginning to break Wall Street’s code of silence, it would be a historic mistake if the S.E.C. and other authorities allowed corporations to systematically dismantle this landmark investor protection reform through private agreements and legal bullying. If their rights are protected, in the coming years, enforcement records will be broken and many of the S.E.C.’s most significant cases will come from courageous whistle-blowers. More important, whistle-blowers will become the enforcers of a new culture of integrity on Wall Street that deters future violations and restores the public’s trust in our financial system.