Peter Avsenew, a male escort, shot Stephen Adams and Kevin Powell dead in 2010 after being welcomed into their home in Wilton Manors.
The couple had taken him in weeks before their death after he posted an ad on Craigslist, according to 10 News ABC.
After shooting the couple, Avsenew stole their money, credit cards and car, went shopping for outdoor supplies and fled to the north of Florida, where his mother eventually turned him in.
Mr Adams and Mr Powell had been together for almost 30 years and their bodies were found wrapped in blankets the day after Christmas Day.
Avsenew showed no remorse or reaction when the death sentence was handed down to him, but he later gave the middle finger to the families of Mr Adams and Mr Powell as they left the courthouse.
In response to the disrespectful gesture, Missy Badget, sister to Mr Adams, said: “After what happened in that courtroom just now, I’m happy that he’s being put to the death penalty.”
Marci Craig, Mr Adams’ other sister, added: “In my heart of hearts, I knew that he was making that gesture to us.”
The sentence was delivered on Friday, with jurors spending Thursday morning hearing the closing arguments from the state and from Avsenew, who represented himself.
In his closing statements he told the jury that he had “no regrets in his life”.
“My job here is simple. I don’t have to prove anything to you as clearly the state’s proven that,” Avsenew said.
“All I have to do is be here and behave. It’s up to you to decide life or death based on the information provided to you throughout this entire trial.
“I have no regrets in my life and I am proud of the decisions I’ve made.
“No one really knows what happened that day. Everyone can speculate what ifs and maybes until they’re blue in the face, which they’ll never really know.”
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