Theron spent Tuesday night in cells at Harare central police station after being questioned for most of the day over his presence at the accident shortly after it happened, said CFU director Hendrik Olivier.
He was being charged with "defeating the course of justice"by taking pictures in the presence of police of the damaged vehicle and the scene, he said.
Susan Tsvangirai, 51, was pronounced dead on arrival at the nearest hospital after the vehicle she and her husband were travelling in was side-swiped by an oncoming truck about 100 kilometres south of Harare, causing it to roll three times.
The Movement for Democratic Change (MDC) leader received head and neck bruising.
Tsvangirai, who shares power with President Robert Mugabe in a coalition government inaugurated on February 13, said the collision was an accident following speculation among his followers of a politically-motivated attempt on his life.
CFU vice-president Theron lived on a farm only 10 kilometres from the scene of the accident, which explained why he had arrived there before police, relatives said.
He had been called by officials in the MDC to film and photograph the scene, to provide a record in case of an inquiry. Police arrested him then and confiscated his camera and video recorder but released him after a few hours. His equipment is still held by police. (EarthTimes)