The California Air Resources Board sent a letter to ProPublica challenging our recent stories on flaws with that state’s forest carbon offset program. Our investigation, which was co-reported and published with MIT Technology Review, reported on a recent study from the nonprofit CarbonPlan, which found that the program had issued up to 39 million carbon credits without real climate benefits.

The first story focused on the study’s main conclusions, and the second story was about the debate over how to ensure additionality — that the program brought about carbon savings that wouldn’t otherwise have happened. The board has not asked for any corrections. Its full letter is available here. The Massachusetts Audubon Society, which sold carbon credits that were ultimately purchased by California polluters under the offset program, also issued a statement, available here.

Below, we provide responses to specific points in the letter from the California Air Resources Board:

The California Air Resources Board does not agree with the conclusions of the April 29, 2021 or May 10, 2021, ProPublica stories on California’s U.S. Forestry Compliance Offset Protocol, or the CarbonPlan study on which those conclusions are based. Forestry projects operating under California’s protocol have removed more than 180 million tons of CO2 from the atmosphere since 2013. California’s forest offset protocol has been developed with extensive public, stakeholder and scientific input through a lengthy public process required by California law. Improved science and additional public input have resulted in updates twice since 2011.

The primary goal of the protocol is to guide project operators through a process which ensures that the carbon their forests remove from the air is additional to any that might be removed under a business-as-usual forest management plan. If the sequestered carbon cannot be verified as additional, it cannot be credited under California’s program. That definition and the methods for determining additionality and implementing it in the baseline calculations have been upheld in court.

Despite this, CarbonPlan and Propublica claim that the California forestry protocol showers projects with millions of “ghost credits” which equate to phony carbon reductions. Yet neither CarbonPlan nor Propublica offer a single grain of proof that any of their claims of cheating are true.

We did not use the term “cheating” in the story. Indeed, we noted that the practices we described are allowed under Air Resources Board’s rules. Our story also states that the study did not examine the intent of any individuals, and that forest owners “can benefit from flaws in the rules whether they intended to or even know about them.”

The first story did raise the concern that some project developers may deliberately exploit the rules to maximize the carbon credits they can earn in ways that could overstate the climate benefits of projects. We referred to this as gaming and cherry-picking.

Overall, the study found the program had produced between 20 million and 39 million credits that don’t achieve real carbon savings.

The CarbonPlan study bases its claims on comparison of the California protocol against the study’s own definition of additionality, and its application to their study’s calculations, specifically with respect to baselines for crediting. CARB sets a baseline to determine any increase in stored carbon. Any increase above that baseline is additional and creditable.

The Air Resources Board sets regional averages for the amount of carbon stored in certain forest types across different parts of the country. Landowners can receive carbon credits, which they can sell, based on the difference between the amount of carbon stored in their land versus the regional average.

In CarbonPlan’s study, the researchers assumed that every project was 100% additional — that is, that every landowner would have otherwise logged their land without the offset program. Their analysis of regional averages is based on ecological and statistical flaws in how the board defined regional average values.

We sent the full study and its methods to the board and other subjects of the story on April 6. Other organizations, such as the Pacific Forest Trust, were able to provide substantive comments on the study’s methodology, and those comments were included in the story. The Air Resources Board has continuously said that any credits above its baselines are additional. Our second story delves into the debate around how to evaluate additionality.

Math can’t hide that this is really about an ongoing disagreement between long-standing critics of the cap-and-trade program with how a regulatory agency defined and implemented additionality through a multi-year public process. The concept of additionality and calculating a baseline are intertwined.

The Air Resources Board does not name the “long-standing critics.” However, in correspondence with ProPublica and the MIT Technology Review, the agency criticized the involvement of Barbara Haya, one of the study co-authors. To question her research, the state’s Air Resources Board focused on Haya’s alleged participation in a 2012 lawsuit. The lawsuit was filed by two environmental groups, which challenged how the board evaluated additionality in its offset program. ProPublica researched Haya’s role and found the board’s characterization misleading.

In 2019, in response to separate inquiries from reporters Lisa Song and James Temple, who were working on independent stories about offsets, board staff members said that Haya was involved with the lawsuit. On Nov. 12, 2019, Clegern told Song that Haya was “the technical consultant” on the case.

Song checked with Annie Beaman, director of advocacy and outreach for Our Children’s Earth Foundation, one of the plaintiffs. Beaman said Haya “was not involved in the CARB lawsuit in any way. The opening trial court brief cited her work once, but not as an expert witness or consultant.” Song also called Haya, who said she’d had conversations with people involved in the lawsuit but was never paid as a consultant.

For these current stories, Song also spoke to one of the plaintiffs’ attorneys, George E. Hays. He said the case cites Haya’s research, and he remembers talking to her about offsets, but said she was not part of the case, and never acted as a consultant or expert witness.

Haya confirmed in an email that “lawyers involved with the case contacted me with questions about California’s offset program which I answered, as I do for many people as one of the few academic experts in this complicated field.”

She also said she had been a member of Citizens Climate Lobby, a grassroots organization that was another original plaintiff in the case, but that “the organization's main work, and my membership with the organization for a brief time, had nothing to do with their law suit.”

She added that “I have never brought anything forward in litigation,” and said the board is “using a false statement about one of the study’s authors to try to discredit that author and the whole study.”

The non-peer reviewed CarbonPlan study and ProPublica’s stories hold California’s forest protocol to a standard and definition of additionality that is neither acknowledged nor proven. It is a paper theory, while CARB’s forest offset program operates with a set of accepted, best forestry management practices under a protocol that has been operating for nearly a decade.

The story explains that the study has not yet been formally peer-reviewed, as it was only submitted for consideration to a scientific journal a few weeks before we published our first story. It also explains, in detail, the steps the news outlets took to check the quality of the study. We sent the study to four different scientists with expertise in climate change, the carbon cycle and/or forest ecology for review. All of them praised the study and its methodology. Some of them offered minor suggestions, which were incorporated into the final study, but these did not change its overall findings.

CarbonPlan researchers explained their rationale for openly publishing their findings, data and methods, and how they implemented their own form of independent review, here.

In addition to reducing carbon emissions, California’s forest protocol helps to keep in place hundreds of millions of healthy trees. Native American tribes are using proceeds from the sale of forest offsets to buy back and restore traditional tribal lands and forests, while the full array of compliance offset protocols bring into the cap-and-trade program economic sectors which would otherwise go unregulated.

The story explains, in depth, the co-benefits of the offset program and how the proceeds have helped boost conservation and the tribes’ efforts to buy back their lands.

As we noted in each of our responses to ProPublica’s multiple rounds of emails, credits issued to projects that meet the U.S. Forest Protocol requirements represent real, quantifiable, permanent, verifiable, enforceable, and additional CO2 reductions.

This is reflected in the stories, which state that the Air Resources Board defended its program and disputed the central thesis of the study.