The government relies on scientific analysis and research in order to create sound public policy. Unbiased research not only pushes the government to make decisions that are guided by facts — it also increases public trust in the policymaking process.

But government science is increasingly coming under the threat of politicization and abuse by actors in the executive branch. A new report released by the bipartisan National Task Force on Rule of Law & Democracy at the Brennan Center highlights how recent administrations have suppressed and manipulated research by scientists in the federal government in order to hide evidence that their plans and policies are flawed, underscoring the need for stronger laws that protect scientific integrity. It also outlines ways to stop this from happening in the future.

Here are five times the Bush, Obama, and Trump administrations undermined scientific integrity by interfering with the findings of federal government researchers for political reasons.

NASA political appointees censored agency’s top climate scientist

James E. Hansen served as director of NASA’s Goddard Institute for Space Studies for more than 30 years, where he had long issued public warnings about global warming. On at least one occasion, a political appointee in the agency’s public affairs office denied a media request to interview Hansen, saying that his job was to “make the president look good.”

NASA’s attempts to censor his research and other climate data were scrutinized during a House oversight committee hearing and in an inspector general’s report, which found that NASA’s public affairs office repeatedly “managed the topic of climate change in a manner that reduced, marginalized, or mischaracterized climate change science.”

The interior secretary cherry-picked data to promote drilling in a wildlife refuge

A central pillar of President George W. Bush’s energy plan involved a push to open Alaska’s Arctic National Wildlife Refuge (ANWR) to oil drilling. In 2001, then-Senator Frank Murkowski (R-AK), who was the chair of the Energy & Natural Resources Committee, asked Interior Secretary Gale Norton to provide official research from her department on how oil drilling would impact ANWR’s Porcupine caribou herd. Norton delegated the requested research to the U.S. Fish and Wildlife Service (FWS), which has expertise in this issue.

Norton’s office, however, substantially rewrote FWS’s findings before delivering them to Congress, according to an inquiry by the nonprofit organization Public Employees for Environmental Responsibility (PEER). FWS officials said that Norton had cherry-picked data that supported her own stance on oil and gas development, ultimately downplaying how drilling would likely affect the caribou. The altered report included changes to key numbers, omitted data, and misleading descriptions of the availability of data. Norton later admitted to making a “mistake” in her submission to Congres, which explained some but not all of the changes that were made.

The EPA downplayed fracking impacts on drinking water

In recent decades, the oil and gas industry has rapidly increased its use of hydraulic fracturing, also known as “fracking,” as a method for fossil fuel extraction. The process involves injecting large quantities of water, chemicals, and sand into the ground at high pressure to fracture shale rock, thus releasing previously trapped oil and gas to the surface. In 2009, Congress urged the Environmental Protection Agency (EPA) to conduct a study on the impact of fracking on drinking water in the United States.

The agency released a draft report of the five-year study in June 2015, which included a statement that downplayed the risks of fracking in its executive summary and accompanying press release: “hydraulic fracturing activities have not led to widespread, systemic impacts to drinking water resources.” An investigation by APM Reports and Marketplace found that the phrase was inserted as a late addition to the report’s executive summary, contradicting earlier drafts that emphasized more clearly incidents in which fracking had in fact contaminated drinking water. After EPA scientists and environmental groups challenged the edits, the controversial statement was removed from the final version of the report, which concluded that drinking water can be affected at any stage of the fracking process. This conclusion was based on a review of more than 1,200 previously cited scientific sources, as well as new research conducted for the report and an independent peer review by the EPA’s science advisory board.

Interior Department officials edited out border-wall analysis from wildlife experts

One of Donald Trump’s major campaign promises during his 2016 presidential run was the construction of a wall along the U.S.-Mexico border. Shortly after assuming the presidency, Trump followed up on that campaign promise by signing an executive order calling for the immediate construction of the proposed wall using federal funding.

In August 2017, U.S. Customs and Border Protection (CBP) requested input from FWS on how the construction of a section of the wall in southern Texas that would cross through a federal wildlife refuge would affect animals in the area. In an initial draft of the response letter, a group of career scientists at FWS, including biologists and wildlife managers, warned that the wall could damage wildlife habitats in the ecologically diverse region, which is home to rare species including ocelots and jaguarundi. The scientists ultimately advised against the construction of a wall in the area.

That recommendation, however, never made it to the CBP. According to documents released under the Freedom of Information Act (FOIA), officials in the Interior Department stripped the final letter of the wildlife experts’ recommendation against building a wall, along with other warnings about potential impacts of its construction. Prior to the drafting of the letter, Interior Department officials had indicated to FWS personnel that then Interior Secretary Ryan Zinke “has indicated we are to support [President Trump’s] border security mission.”

Intelligence analyst blocked from submitting written testimony on climate change

In June 2019, Dr. Rod Schoonover testified before the House Intelligence Committee in a hearing on the national security implications of climate change. But Schoonover, who works in the State Department’s Bureau of Intelligence and Research, was blocked by the White House from submitting his written testimony, in which he warned of the potentially disastrous effects of climate change.

In his written testimony, Schoonover said that, “absent extensive mitigating factors or events, we see few plausible future scenarios where significant — possibly catastrophic — harm does not arise from the compounded effects of climate change.”

The supposed rationale for blocking the written testimony was that the findings did not align with the Trump administration’s official stance on climate change. Shortly after the incident, Schoonover resigned from the State Department in protest. Lawmakers voiced concern about the missing written testimony and sought information concerning the circumstances under which it was withheld.

For more examples, read the new report from the National Task Force of Rule of Law on Democracy. The report also includes proposals to safeguard the integrity of scientific research and analysis by the federal government.