Bennett says he felt helpless, lying handcuffed on the ground "facing the real-life threat of being killed."
"All I could think of was, 'I'm going to die for no other reason than I am black and my skin color is somehow a threat,'" he writes.
He says they loaded him into the back of a police car, where he sat "until they apparently realized I was not a thug, a common criminal or ordinary black man but Michael Bennett a famous professional football player."
TMZ posted video of part of the encounter, which shows an officer handcuffing Bennett on the ground as he protests, "I wasn't doing nothing!"
A 31-year-old in his ninth season in the NFL, Bennett told ESPN last month that the violence in Charlottesville, Virginia, linked to a white nationalist rally persuaded him to sit during the national anthem for the entire 2017 season. He grew up in Houston and recently announced a campaign to raise relief funds for those affected by Hurricane Harvey.
"I have always held a strong conviction that protesting or standing up for justice is just simply, the right thing to do," he writes. "[E]quality doesn't live in this country and no matter how much money you make, what job title you have, or how much you give, when you are seen as a '[N*****], you will be treated that way."
Las Vegas police told The Associated Press that they were checking casino and police body camera video, as well as written reports.
"Without looking at video footage or reading any reports, we can't say yet what happened," Officer Jacinto Rivera told the news service.
"We think there was an unlawful detention and the use of excessive force, with a gun put to his head," Burris told the AP. "He was just in the crowd. He doesn't drink or do drugs. He wasn't in a fight. He wasn't resisting. He did nothing more or less than anyone in the crowd."
Colin Kaepernick, the former San Francisco 49ers quarterback who started the national anthem protests last season, tweeted his support of Bennett.
"This violation that happened against my Brother Michael Bennett is disgusting and unjust," he wrote. "I stand with Michael and I stand with the people."
Bennett says the system failed him. "I can only imagine what Eric Garner, Michael Brown, Trayvon Martin, Tamir Rice, and Charleena Lyles felt," he writes.
Martin, a black teenager, was fatally shot by a neighborhood watch volunteer. The others, who were also black, were killed by police.
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