Protesters have gathered outside an Istanbul court in a rally for justice for Mehmet Ayvalitas.
The 20-year-old was killed when a vehicle rammed into a group of demonstrators as they protested against an urban development plan for Gezi Park close to Taksim Square in the city.
Seven people died during the protests with thousands injured.
The victims mother Fadime said outside the court: “I will speak in front of a judge for the first time in my life, I am full of emotion. The emptiness he left is so big and it’s getting bigger. Nothing can take his place.”
As the trial of the alleged driver got underway a number of protesters tried to force their way into the courthouse after members of Mehmet’s family were refused entry.
Demonstrations against the Gezi Park construction plan spread across Turkey and became a collective call to keep Turkey secular and against the perceived authoritarianism of Prime Minister Recep Tayyip Erdogan.