WASHINGTON (AP) — Journalist and scientific organizations accused the Environmental Protection Agency on Tuesday of attempting to muzzle its independent scientific advisers by directing them to funnel all outside requests for information through agency officials.

In a letter Tuesday, groups representing journalists and scientists urged the EPA to allow advisory board members to talk directly to news reporters, Congress and other outside groups without first asking for permission from EPA officials. An April memo from the EPA’s chief of staff said that “unsolicited contacts” need to be “appropriately managed” and that committee members should refrain from directly responding to requests about committees’ efforts to advise the agency.