A national alliance of government employees, including state and federal scientists, warned President Donald Trump to protect scientific integrity or face a relentless wave of public backlash.

Jeff Ruch, executive director of the Public Employees for Environmental Responsibility, urged Trump in a letter Tuesday to take over President Barack Obama’s unfinished mission of improving standards for government scientists. Censoring science, Ruch added, “is doomed to fail and will create needless backlash.”

“Simply put, administration attempts to manipulate science to fit its official talking points will inescapably fail, automatically be leaked and subject your White House to a daily drip-drip-drip of bad, off-message news coverage,” Ruch wrote.

As The Huffington Post reported Monday, Trump’s actions during his first days in office, including Friday’s executive order on immigration, are creating havoc that some say could send scientists and academics overseas.

White House science adviser John Holdren, an Obama administration holdover, addressed this very issue in an interview Monday with the journal Nature. If Trump’s immigration ban stays in effect, he said, “it will damage a wide array of collaborations in science and technology around the world.”

In his letter to Trump, Ruch wrote that Obama “only established a beachhead on scientific integrity with little impact on actual agency practices.” Gaps in those policies, he noted, are highlighted in a December assessment by the White House Office of Science & Technology Policy Institute.

To see just how quickly an attempt to interfere with science can backfire, Ruch told Trump he need look no further than his own administration. Last week, Doug Ericksen, communications director for Trump’s EPA transition team, said the agency planned to review all of its scientists’ studies on a “case by case basis” prior to publication, National Public Radio reported. The news sparked immediate outrage among scientists and environmentalists.

“The only way to quell the quagmire of unending controversy on issue after issue is to establish strong, clear and uniform guidelines ensuring a transparent paper trail and allowing scientific information to be freely shared,” Ruch wrote to Trump. “Mr. President, we urge you to make lemonade out from an entire lemon orchard of scientific conflict in your path. You can do this only by championing openness as your official policy regarding science.”

This isn’t the first time the scientific community has issued a warning to Trump.

In an open letter in November, more than 2,300 scientists, including 22 Nobel Prize recipients, called on the president and Congress to sufficiently fund scientific research and “support and rely on science as a key input for crafting public policy.” They promised to hold accountable anyone ― Trump included ― who seeks to undermine the role of science in policymaking.

Read Ruch’s full letter here.