The analysis by The New York Times of the Trump administration’s record in enforcing environmental regulations was based on data compiled by the Environmental Protection Agency and publicly available in its Enforcement and Compliance History Online database.
Because the online records are not always immediately updated, the analysis also accounted for cases pursued under Mr. Trump that were available in E.P.A. and Justice Department news releases, the federal register, court documents and other public sources.
The analysis covered a period of 266 days in each of the Trump, Obama and George W. Bush administrations.
Using information from a public database, the analysis covered activity during the first 266 days of E.P.A. leaders in the Trump, Obama and Bush administrations.