Denver police plan to encrypt the department’s radio traffic, blocking public access.

The Denver Post reports that the department will require news media to sign an agreement before gaining access to the radio traffic, which journalists use to report on breaking news and police activity.

Denver Police Chief Paul Pazen says the change will keep suspects from listening to authorities’ communications and protect personal information such as addresses. Pazen says he hopes to make the switch in mid-April.

Colorado Press Association CEO Jill Farschman says she is concerned that the agreements required of media organizations are a piecemeal approach.

She also worries about the high cost of new scanners needed to hear the encrypted radio traffic.

Nearly 30 other Colorado police agencies block public access to their communications using encryption.