The police department issued two disorderly conduct citations on the day of the fight, one to an adult and another to a minor.
Eyewitness News is now hearing from one of the people caught on video who appears to get hit by Rivas. That man is 23-year-old Taylor Alexander. He said charges should be pressed and sees only one way to look at what happened at the Island Bay Resort apartment last week.
"I think everything he did was wrong, and he used excessive force," Alexander told ABC13.
He said they weren't at the pool deck brawl, just nearby. When things seemed to be calming down, he, his teen brother, and his mother tried to walk away but were stopped.
RELATED: Only on ABC13: New video shows off-duty Galveston officer involved in 2nd fight at kid's pool party
"Rivas yelled for us to stop. My little brother, the youngest, 15, turned and was super compliant, 'Yes sir,' at that point, (Rivas) grabs him by the back of the neck and threw him to the ground," Alexander recalled.
That's where the new video obtained by ABC13 picks up. Alexander said this video shows Rivas pinning the teen down before getting in their mother's face.
"He got up in my mom's face, and my mom has had two surgeries; she just had her neck fused a few months ago, and my thought process was, 'If he takes him down the same way he did, it's going to paralyze her,' so I jumped in between them," Alexander said.
Rivas flashes his badge and can be heard yelling expletives just before the video stops. Alexander said in the moments after the video, an officer started to detain him; Rivas pulled an arm back and swung for his face.
"It all happened so fast it's not super clear, but I think he took a swing at me. Well, I know I was struck three times, once in the face and twice in the back of the head," Alexander said.
Taylor's mother, Lori Lozano, told ABC13 that she thinks Rivas' behavior was uncalled for.
"He is a bad apple. He's a loose cannon and very dangerous," Lozano said.
Alexander said he was put in the back of a police car when Rivas got in the front seat, and he did not appear to realize he was in the back.
"He came in, turned on the AC, put his hands on his head like this, and then he got out and left," Alexander said.
Alexander was released and checked by EMS. He said he's filed a complaint against Rivas, wants to see charges brought against him, and said he should be removed from the force.
Police and the apartment complex continue to be divided on why Rivas was at the pool. Police said he was working as an off-duty courtesy officer, but on Tuesday, the leasing office said they are standing by their statement from last week that Rivas was not an employee of the complex.
The Galveston Police Department said Rivas has no prior disciplinary action listed in his employee file.
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