Cairo Criminal Court acquitted Sunday low-ranking police officer Mohamed Ibrahim Abdel-Moneim, known as El-Sunni, accused of killing a protester in front of Al-Zawya Al-Hamra police station during the January 25 Revolution.
El-Sunni was sentenced in October 2011 to 10 years in a high security prison. He later won on appeal and was ordered to be retried.
In a different case, the defendant also received a life sentence in absentia for participating in the killing of 18 protesters and injuring three others on 28 January 2011, known as the "Day of Rage."
El-Sunni later turned himself in and his sentence was reduced to five years, which he is currently serving.
El-Sunni earlier accused the police and Ministry of Interior of scapegoating him.
At least 846 civilians were killed and over 6,000 injured during the 18-day uprising against the regime of Hosni Mubarak that began on 25 January 2011.
Several policemen were known to have fired on unarmed demonstrators during the revolution. To date, however, Egypt's judiciary has failed to convict a single policeman of murder.
The lack of convictions has continued to be a source of frustration for victims' families, who have repeatedly complained that officers said to be complicit in their relatives' deaths continue to go unpunished.