There has never been anything in America like 60 Minutes.

The Sunday tradition is the most successful program of any kind in history. For more than a decade, its innovative growth on every major online platform has extended its reach to countless millions around the world. This spring, at the end of our 58th season, 60 Minutes grew rapidly with an unheard-of 9% jump in viewers on CBS.

“60” has been the number-one program in America for decades because our beloved audience finds integrity, quality, and humanity in our stories. When stewardship of the program passed to my colleagues and me, our responsibility was to expand energetically into a new age of media technology while preserving the values our audience expects. Now, the new owner of our network is casting this legend aside, apparently to curry a moment of favor with the Trump administration.

The waste is heartbreaking.

Last month, 60 Minutes lost its DNA when our entire senior leadership and two of our best on-air correspondents were cruelly fired without cause. Good people were silenced because they stood up for our audience. They stood for fairness against the forces of political bias; they stood for professionalism against chaos.

For my part, new management has instructed me to inject falsehoods and bias into a politically sensitive story. I’ve been told to include assertions that are unverified. To date, in every case, I have managed to ignore these instructions or refuse them. Recently, politicians have been invited to choose correspondents for interviews on the broadcast. Giving politicians control over 60 Minutes interviews is not how this is done. Finally, incompetence and unprofessionalism in the new management have wreaked havoc. In a case involving one of my stories, the entire program came within 19 minutes of not getting on the air at all.

At 60 Minutes, we have fought harder than anyone knows to save the program that became an American icon. We owed that to our millions of viewers. I am deeply moved by the thousands of wishes we have received to “keep up the good fight.” Most of the men and women of CBS News are still in that fight. But now the collapse of values at the top has become untenable. The leadership of 60 Minutes is no longer recognizable. The principles I hold dear are gone, and so I must leave as well.

I depart after 37 years at CBS with one emotion—a heart brimming with gratitude for the men and women of CBS News who encouraged and enriched my work, very often at the risk of their own lives. I pray for a day when those people and their ideals are honored again—a day when sanity, competence, and courage return.

Scott Pelley