Customers asked this question earlier this year when Facebook CEO Mark Zuckerberg’s lobby group FWD.us released ads supporting the dirty tar sands oil pipeline, Keystone XL, and again this summer when news broke that Google hosted a fundraiser for Oklahoma Senator Jim Inhofe, the zealous leader of the climate denial movement who famously called climate change a “hoax” on the Senate floor and has compared the environmental movement to the Third Reich.

Both Google and Facebook also gave money to support the Competitive Enterprise Institute, an anchor tenant in the climate science denial propaganda machine that’s been funded by the likes ofExxon, theKoch Brothers, andDonors Trust, the dark money ATM for ultra-conservative moneyed interests.

Google and Facebook have been two of the most forward-looking U.S. companies when it comes to clean energy, using their influence to push governments and utilities in the states where they operate toward climate action, and giving their users reason to believe they’re not just in business to make billions at any cost. They’ve been renewable energy champions in North Carolina, Iowa, and Oklahoma, and they’ve been very public about being “Green.” They also obviously have to protect their interests on a range of issues in Washington, but many of their billions of users - and their own employees - hoped they could do it without sacrificing their climate leadership.

It appears that Google, Facebook, and Microsoft - who supports the American Legislative Exchange Council, yet another group that peddles climate disinformation - are in serious danger of letting themselves get caught playing a cynical game, and in so doing, letting their users and their employees down. These are solutions companies - full of engineers and innovators - and while they are in the business of business, science has always been at the core of what they do.

The news about Google and Senator Inhofe is particularly troubling. Beyond simply speaking out of school on the Senate floor, Inhofe has used his position as ranking member of the United States Senate Committee on Environment and Public Works to block climate legislation, kill debate, and otherwise keep the United States from taking any meaningful Congressional action on the defining crisis of our time. So why would “Don’t Be Evil” Google commit its brand to raising money for someone so clearly on the wrong side of the climate fight? The reality is that technology companies have realized that they have to pay attention to who controls Washington, and now these companies are among the biggest players in providing the money that makes Washington go round.

For Google, which has a data center in Oklahoma that it powers with clean energy, keeping Inhofe in power is completely inconsistent with all of the company’s work as a climate leader. Greenpeace and others have praised Google’s clean energy leadership; you can imagine my shock to see a company we admire act so cravenly.

Until we pass campaign finance reform, companies are going to spread their money to as many politicians as they can to help protect their interests. But even in an obviously corrupt operating environment, companies that recognize the reality of climate change and want to lead on fixing our future should have a red line they won't cross. We propose the No Deniers Rule as a good starting place for any company that wants to be on the right side of history in the climate fight.

If companies like Google, Facebook, and Apple refuse to give to Denier politicians and organizations like the Competitive Enterprise Institute, then those people will quickly learn that if they want the support of America’s vanguard companies, they can't be on the wrong side of climate history. No Deniers Allowed.

Then users and employers of Google, Facebook, and others would be able to stay proud of all that those companies have done for clean energy, without worrying that the companies are undermining that work by helping keep climate deniers like Inhofe in power.