As the new NFL football season gets under way in the United States, it is not what is happening on the field that is attracting all the attention, but an act of defiance on the sidelines.

When the national anthem played before kick-off, the San Francisco 49ers quarterback Colin Kaepernick kneeled down, instead of standing up like everyone else.

He was protesting against racial oppression, police brutality and social injustice.

His controversial snub is winning him praise and support. Other athletes are following suit, either by also kneeling or raising their fist. They are being accused of being unpatriotic.

It is adding fuel to the fire of the race relations debate, especially as US police are scrutinised over allegations of using excessive force against black people.

Can their their highly visible and controversial protests bring about change?

Presenter: Martine Dennis

Guests:

Kevin Alexander Gray - Civil rights activist, and author of The Decline of Black Politics: From Malcolm X to Barack Obama

Kris Marsh - Sociologist at the University of Maryland

Vincent Warren - Executive director at the Center for Constitutional Rights, New York

Source: Al Jazeera News