Three police officers accused of gross misconduct are appearing before a hearing panel this week.
PC Hugh Flanagan, PC Caroline Irwin and PC David Stamp are accused of gross misconduct for actions leading up to a crash in which two people died in icy conditions on the A413 near Wendover on March 4 2014.
The Thames Valley Police hearing is being held at Shaw House in Newbury, and is scheduled to last two weeks.
The crash claimed the lives of Carl Bird, and father of two Malcolm Tindall from Aylesbury - as well as seriously injuring a female passenger travelling with Mr Bird.
Mr Tindall’s family campaigned for an investigation into what happened from the start, and have been present at the hearing.
Earlier this month the Independent Police Complaints Commission announced that they had investigated the events leading up to the crash, and had recommended that the officers involved face a misconduct panel.
The first two days of the hearing were taken up with legal arguments, and the panel is expected to start hearing evidence properly tomorrow.