NYPD detectives have interviewed the motorcyclist whose helmet cam captured the confrontation, according to Deputy Commissioner John McCarthy. They tracked the unidentified biker to his home in Bellport, Long Island, and have the video.
Police are also looking at a 2011 video that shows a separate case of biker violence. In it, riders appear to surround and antagonize a motorist.
Law enforcement officials said they are examining the footage frame by frame, looking for possible patterns.
Mieses' family says the real victim of the confrontation is the hospitalized biker.
"All of his ribs are fractured. His lungs are so badly bruised that he's still on a ventilator," Yolanda Santiago, his mother, told CNN affiliate WCBS.
His wife, Dayana, told CNN affiliate WBZ that Mieses got off his bike to help the SUV driver.
"And whatever he did, he got scared, he peeled off, and he paralyzed my husband on the way," she said.
At the vigil Wednesday night, the attendees raised almost $400.