On the 10th anniversary of the Telecommunications Act of 1996, many are evaluating its legacy. The chairman of the Federal Communications Commission, Kevin Martin, and two of the architects of the act, Tom Bliley, former chairman of the House Commerce Committee and Senator Pressler, a former chairman of the Senate Commerce Committee, will meet tomorrow at the American Enterprise Institute to reflect on the impact of the policy change.

The act’s reputation has waxed and waned with the fortunes of the communications sector. From 1996 to 2000, the value of publicly traded securities in the industry grew by hundreds of billions of dollars, and the telecom act was adored. Since 2001, the communications sector has struggled, and so has the act’s reputation.

Under the law, competition was permitted as a matter of federal law. In 1996 and 1997, the FCC, as dictated by the act, wrote hundreds of pages of new rules designed to be the foundation for a new federal policy on communications competition.

As it had for decades, the FCC wrote the rules by reserving for itself the prerogative to administer them, enforce them, and adjudicate many resulting disputes. The road to the future of telecommunications passed through the FCC. Financial institutions funneled billions of dollars to hundreds of telecommunications firms, new and old, that built business plans around the new FCC rules.

Disaffected parties ultimately mustered the courage to take the FCC to court. Some courts refused to overturn FCC rules out of deference to the commission’s expertise or broader discretionary authority. But other federal courts overturned one new FCC rule after another. Businesses that had planned their futures around those rules were undermined. The rule of law in telecommunications, it turned out, was neither predictable nor forgiving.

Courts did not overturn the provisions of the act itself, only the FCC-written rules under it. It is difficult to imagine how the telecommunications sector and our economy would look today if the rules under the act had been accurately and predictably written, to withstand court challenges. At least some of the financial carnage of the past decade might have been avoided. Rather than shunning the telecommunications sector as a lawless wasteland, investors today might still be investing billions of dollars in new whiz-bang technologies.

Eighteenth-century political observers from Locke to Madison knew that individuals charged with all of the responsibilities of writing laws, enforcing them, and adjudicating disputes under them would do none of them well. Indeed, the experience was that even capable individuals would perform poorly when granted all the powers of government. The separation of powers in our Constitution was no coincidence.

Today we take for granted that we have inherited a government based on separation of powers. But some government agencies exercise more than one of the powers of government. These agencies include the Securities and Exchange Commission, the Federal Reserve Board, the Food and Drug Administration, the Environmental Protection Agency, and others. Individuals and businesses dissatisfied with these agencies’ decisions are all too familiar with their extraordinary powers. Congress holds hearing on rules beyond their power to influence. Few parties have the courage to challenge them, and fewer courts are willing to second-guess either their expertise or their broad authority.

Many voices now demand that Congress rewrite the telecom act to favor one industry over another under the pretext that current law is outdated and its intent unfollowed. Messrs. Bliley and Pressler heard all of these familiar pleas – 10 years ago. Until Congress closely examines the concentration of powers in government agencies, calls to rewrite laws will keep coming.

Mr. Furchtgott-Roth is a former commissioner of the Federal Communications Commission. His most recent book, A Tough Act to Follow? The Telecommunications Act of 1996 and the Separation of Powers (AEI: 2006) will be presented tomorrow at the American Enterprise Institute.