The collision happened on the N7 outbound in Kingswood, Co Dublin, in the early hours of September 21st.
The man, aged in his late 20s, is being detained at Clondalkin Garda station.
Advertisement
Gardaí are appealing for anyone who was travelling on the N7 northbound or southbound between Newlands Cross and Kingswood between the hours of 12.15am and 12.45am on September 21st to contact them.
Officers are particularly keen to speak to drivers of HGVs and taxi drivers who may have been travelling along the route.
Any motorists who may have camera, including dashcam, footage that may assist in the investigation are asked to make it available to gardaí.
