Bob Graham was a U.S. senator from Florida from 1987 to 2005. He served as chairman of the Senate Select Committee on Intelligence from 2001 to 2003 and as co-chairman of the Joint Inquiry Into Intelligence Community Activities Before and After the Terrorist Attacks of September 11, 2001.

Since the Justice Department named a special investigator, Robert Mueller, to handle the government's official inquiry into Russian meddling in the U.S. election, the weight of public expectation has largely fallen on his shoulders. While the two congressional panels, the Senate and House intelligence committees, continue to hold hearings and question witnesses, including Paul Manafort and Jared Kushner, both are led by members of a party that is, with the exception of Charlottesville, skittish about criticizing the president. The greatest hope for an aggressive and impartial inquest seems to lie with Mueller, whose bosses have either recused themselves from the Russia probe (as Attorney General Jeff Sessions did) or volunteered that he would have autonomy to follow the facts wherever they led (as Deputy Attorney General Rod Rosenstein did). The pressure, it seems, is off Congress to act as the primary body holding the president to account.

This is a dangerous sentiment. The two intelligence committees should act as if their investigations will be the final (and possibly the only) ones — because they may be. President Trump has worked hard to undermine Mueller's effort, not only berating it as beholden to a partisan "hoax" but also belittling Sessions on Twitter in a transparent attempt to force the attorney general's resignation. That way, the president could replace him with an appointee who would stymie Mueller's work. A central role for Congress is the only real way to guarantee a full report, with conclusions and recommendations, for the American people.

I oversaw a similarly complex and politically fraught inquiry as co-chairman of the joint congressional inquiry into 9/11, so I know what it takes — as a matter of resources, time, perseverance and, yes, occasional political courage — to run an investigation of this size and importance. And I know this, too: The congressional intelligence committees, as they are constituted today, are not ready for this burden.

They must tackle three problems.

First, the committees need substantially more capacity. After 9/11, the Senate and House leadership decided to merge the two intelligence committees so they could collaboratively and thoroughly investigate the intelligence issues raised by the attacks. The joint committee had a staff of 24 experienced professionals who were dedicated to the inquiry, independent from the regular professional staff of either the House or the Senate intelligence committee. They'd worked at key intelligence and law enforcement agencies and had knowledge of forensic accounting, investigation and intelligence analysis. Staff director Eleanor Hill had previously prosecuted organized crime for the Justice Department and served as staff director and chief counsel for the Senate Permanent Subcommittee on Investigations.

Given the number of highly classified documents under review, the joint inquiry also had its own secure office space, separate from each chamber's committee office. It had its own budget of at least $5 million, dedicated solely to the one-year inquiry. By comparison, the Senate committee had $8.1 million and the House panel $8.6 million to address regular legislative and oversight responsibilities for the two years of the 107th Congress.

Right now, the Senate has 38 staffers and the House has 31 devoted to the intelligence committees, with budgets for the 115th Congress of $11 million and $12.1 million, respectively. Those personnel and funds are intended to cover all the legislative and oversight work of the intelligence committees, including the Russia investigation. Early in the inquiry, the Senate committee reportedly had only seven staffers working on the probe. It needs many more.

To complete the Russia investigation, the committees need independent staff members who are solely dedicated to this topic: forensic accountants and specialists in international law, financial crimes, counterintelligence investigations, and cybersecurity and coding. Those devoted to Russian meddling should not be regular committee staffers on overtime, unfamiliar with the tasks unique to the Russian inquiry.

After more than six months of separate activity, it is probably too late to merge the current congressional committees. It is not too late, however, to create independent, experienced and substantially larger staffs capable of fulfilling the committees' responsibilities, particularly in a post-Mueller era.

Second, the House and Senate intelligence committees must quickly begin planning for post-Mueller scenarios. Yes, perhaps Sessions will stick around and Rosenstein will continue to guard Mueller's autonomy. But the congressional committees need to devise protocols now that would be activated, if Mueller were fired, to ensure the protection of, and access to, all documents, transcripts, communications and other materials amassed by the Mueller and James Comey probes. The protocols should ensure that these materials are made available to the congressional committees in their original form. If Mueller is dismissed, the congressional inquiry would probably expand, as in the Watergate investigation, to the consideration of impeachment.

Third, Congress must embrace its investigatory role with renewed urgency. The 9/11 inquiry had a deadline of December 2002, the end of the 107th Congress. This investigation has no such finale. But there are serious consequences to procrastination. If Russia has in fact attempted to interfere with democratic elections in Europe, the United States and elsewhere, disclosing that reality and repelling further intrusions are crucial. Preventing future tampering in elections will require the support of an informed American public, which should be told of Congress's definitive conclusions as soon as possible. Any delay in publicly sharing clear and convincing evidence will add to the already staggering distrust of many Americans in their government. (Portions of the 9/11 inquiry report remain classified even today, limiting the public's understanding of the tragic event and its ability to influence policy, especially regarding U.S.-Saudi relations.)

The nation's best option is for Mueller to continue his investigation until it ends, wherever it leads. Should Trump find some way to remove him, it would spark a constitutional crisis unlike anything since Watergate; Congress must be ready for this worst-case scenario. In our system of checks and balances, it has the right and duty to exercise full oversight. Now is the time to start preparing for that responsibility.

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