Have some special interests grown so big and powerful that they can stare down the Department of Justice? You’d hope not, because once bigness and power become an excuse to operate outside the law, we will end up seeing a lot more lawless behavior by the big and powerful. In a nation built on the rule of law and the principle of equal justice before the law—that’s not good.

But once you get big enough, staring down law enforcement becomes a credible strategy. Mighty defendants who can mount “blizzard defense” strategies can put immense pressure on even government plaintiffs. When I brought suit as attorney general against the lead paint industry for poisoning thousands of Rhode Island children, the industry lawyers listed multiple dozens of trial witnesses. It would be malpractice not to depose your adversary’s trial witnesses, so all over the country we went to take depositions. At trial, the industry called exactly zero of those witnesses.   It had been a wild goose chase to exhaust our resources. And that is only one among many heavy-handed maneuvers big defendants can afford.

Powerful interests also bring plain old political pressure to bear. When the Department of Justice was considering bringing a case against Big Tobacco, funding for the department was repeatedly threatened by tobacco interests in Congress, and tobacco industry propagandists and front groups criticized the Department in the media relentlessly about the case. Despite this campaign, the Department of Justice not only brought, but won, its civil case against the tobacco industry, and that put an end to the industry’s fraudulent doubt and denial scheme.

Many have noticed the similarities between Big Tobacco’s strategy of denial and doubt about smoking and the strategy of denial and doubt used by Big Oil about climate change. In some cases, it’s even been the same organizations and individuals involved.

Tobacco was big, but the fossil fuel industry is bigger—it’s some of the world’s biggest companies. And beyond the companies themselves is a massive array of front groups denying and spreading doubt about climate change. It is a beast indeed, numbered by academic researchers at over sixty front groups. It should not be surprising that with hundreds of millions of dollars at stake, the fossil fuel industry has built a complex web of denial to confuse and obstruct lawmakers.

Also very big is the “dark money” apparatus flooding our elections in the wake of Citizens United. Hundreds of millions of dollars are flowing—a “tsunami of slime,” in one reporter’s memorable description—backed both by powerful business interests like Koch Industries (one of America’s largest emitters of industrial waste) and powerful political interests. Both Democrats and Republicans use dark money, but dark money has become the Republican Party’s financial life support system. So challenges to that dark money system will create massive blowback from powerful and ambitious forces.

But it is a system based on making what appear to be false statements to the government, and that is supposed to be a crime, punishable under Title 18 Section 1001 of the U.S. Criminal Code. The apparent falsehood is most clear in the discrepancies between sworn statements made to the IRS by organizations seeking that much-prized dark money status (these statements swear that the organization will not engage in any electioneering activity), and sworn statements made under oath by the very same organizations to the Federal Election Commission and state election regulators that report millions of dollars in actual election spending.

The IRS has been bullied into timidity after its hapless effort to address the dark money problem by segregating out for special scrutiny new applicants with political terms in the organizations’ names. Calls for impeachment of the senior IRS official are routine, and the agency is curled up in a defensive crouch. Across town, the FEC has been ground to a dead stop by its Republican members, who refuse to take up virtually any agency business. So if the Department of Justice is waiting for agency leadership, it will be a long wait.

Climate change looms over our planet; dark money pollutes our beloved democracy. These are two of the epic threats America faces in this century, and both appear to be abbetted by illegal behavior by the interests involved. Has the Department of Justice even taken a look? The Department goes after lots of little guys in what officials call “bread and butter” false statement prosecutions, but against the enormous and powerful interests behind the dark money, there is no sign of action.

I hope the Department of Justice is not reluctant to use its firepower just because the opponents are big and powerful. If climate change is indeed the challenge of our generation, what will be said of a Department that allowed that fraud to run unexamined, to the peril of the planet? At a minimum, we should expect a department that can say, “we gave it a full and honest look, to the very best of our capabilities.”

Whitehouse is a Democrat from Rhode Island.