He said he received them through "a couple different avenues," including social media.
"To me, if something like that were to happen, you've proved my point and it will be loud and clear for everyone why it happened and that would move this movement forward at a greater speed than what it is even now," Kaepernick told reporters on Tuesday. "Granted, I don't want that to happen, but that's the realization of what could happen, and I knew there were other things that came along with this when I first stood up and spoke about it. That's not something I haven't thought about."
The quarterback cited the Friday killing of unarmed black man Terence Crutcher by white police officer Betty Shelby in Tulsa, Oklahoma, as yet more reason for him to speak out. Crutcher's car had broken down on the highway, and his hands were over his head when he was shot.
“You have a situation like Terence Crutcher, where his car was broken down and he was looking for help and got murdered,” Kaepernick said. “That’s a perfect example of what this is about. I think it’ll be very telling what happens with the officer that killed him, what happens with [her] because everybody's eyes will be on [her]. For me, I think one of the things that I've noticed throughout this is there's a lot of racism in this country disguised as patriotism. People want to take everything back to the flag, but that's not what we're talking about. We're talking about racial discrimination, inequalities and injustices that are happening across the nation."
Denver Broncos linebacker Brandon Marshall, one of many athletes inspired to join Kaepernick in kneeling for "The Star-Spangled Banner," said that the nation's reaction to the Crutcher shooting highlights the reason for the protest.
"One thing I have an issue with is people are really, extremely [ticked] off and mad about us kneeling and protesting peacefully. How come they don't have that same type of anger toward the situations that are going on? I think everybody needs to check themselves," he told the Denver Post.
Last week, the linebacker met with Denver Police Chief Robert White to discuss the growing tensions surrounding the situation.
"It just lets me know that we have a long way to go as people," Marshall told the newspaper. "I don't want to go as far as to say people care more about the flag than their fellow man, but it seems like it."