Curtis Reeves, who is charged with second-degree murder, was denied bail during his first court appearance.
The 71-year-old opened fire after asking a man sitting directly in front of him to stop texting several times.
He told investigators he was "in fear of being attacked". The victim, named as Chad Oulson, died in hospital.
Mr Reeves appeared by video link from the Land O' Lakes Jail in Pasco County at the court hearing on Tuesday afternoon.
He was wearing a jail-issued vest-like garment for his own protection "because of the high-profile nature of the case", a local police spokeswoman told The Tampa Tribune.
Mr Reeves faces a possible life sentence if found guilty.Wife injured
The two men, accompanied by their wives, had been watching the previews for a matinee screening of the new war film Lone Survivor in Wesley Chapel, north of Tampa, on Monday, when the row broke out.
Mr Oulson's wife, Nicole, suffered non-life-threatening injuries as she had placed her hand over her husband just as he was shot, sheriff's spokesman Doug Tobin said.
Tampa Police spokeswoman Laura McElroy said Mr Reeves was a captain when he retired from the department in 1993.
Lone Survivor, based on a New York Times best-seller, stars Mark Wahlberg and tells the story of four navy Seals on an ill-fated covert mission against the Taliban in Afghanistan.