WASHINGTON  The inspector general of the Interior Department has found that agency officials often interfered with scientific work in order to limit protections for species at risk of becoming extinct, reviving attention to years of disputes over the Bush administration’s science policies.

In a report delivered to Congress on Monday, the inspector general, Earl E. Devaney, found serious flaws in the process that led to 15 decisions related to policies on endangered species.

The report suggested that at least some of those decisions might need to be revisited under the Obama administration.

Among the more significant decisions was one reducing the number of streams that would be designated as critical habitat for the endangered bull trout and protected from commercial use. That rule is already the subject of a lawsuit by environmentalists.