A petition submitted to Florida Governor Charlie Crist pleaded with him to have pity on Grossman, who is scheduled to be executed with a lethal injection in nine days.
Grossman was 19 when he and his 17-year-old friend traveled to an isolated nature reserve to fire a stolen handgun. The two were approached by wildlife officer Peggy Park, 26, who asked Grossman for his weapon license.
Grossman pleaded with her to let him go, as he was violating his probation for a burglary charge, but she refused. When she tried to call for help over the radio, Grossman hit her 20 to 30 times, and when she tried to reach her weapon and fired one shot, Grossman shot her in the back of the head.
Grossman's friend, Thayne Taylor, served three years in prison for his involvement in the incident, while Grossman himself was convicted of murder and sentenced to death.
Grossman's lawyer appealed to the Florida Supreme Court in a bid to stop the execution, saying that his client did not undergo a psychiatric evaluation during his trial.
Rabbi Menachem Katz, who visited Grossman in jail over the past 15 years, says that the Jewish prisoner has reformed and regrets his actions. If the sentence is implemented, Grossman will be the 25th person to be executed in the state of Florida in the past decade.
Initial information received via Red Email