Mario Jarell Williams was arrested in November when police say he killed his boyfriend, Devon Wade.
Investigators believe Wade, who was a youth mentor and doctoral candidate at Columbia University, asked Williams to leave his Atascocita home multiple times after an argument.
But Williams allegedly got upset and opened fire.
According to friends and family, Williams took his own life last week. He was buried over the weekend.
Deputies: Accomplished LSU scholar killed by boyfriend in Atascocita
Deputies: Accomplished LSU scholar killed by boyfriend in Atascocita
'Don't be angry, don't be sad': Hundreds remember scholar allegedly killed by boyfriend
Memorial service held for Devon Wade
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