Erick Bautista, 22, is facing murder charges in the killing of 40-year-old Winston McKay.
Bautista, police say, is the man caught on surveillance video holding a rifle.
Investigators believe Bautista got in a fight over drugs when McKay was fatally shot., He had just finished celebrating the 18th anniversary of meeting his husband and was walking their dog Milton.
In 2019, his husband Terry Solomon said they had been married for about two years.
"I got the kiss, and next thing I know, I'm getting calls my husband was shot," Solomon said. "I'm questioning myself, like, Lord, why couldn't it have been me? I will never fall in love that way again."
Solomon said McKay was generous and kept to himself.
McKay had worked as a librarian and was taking classes at Mildred Elley College in Lower Manhattan.
Police also arrested Ozjheir McClain, who police say fired the shot during an argument with Bautista.
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