Video: Debbie Dorling speaks about impact of husband Brian's death in White Bikes documentary

A short film focusing on the death of Brian Dorling, killed by a lorry as he rode his bike through Bow Roundabout on his way to work at London's Olympic Park last October, powerfully captures the impact of the death of a cyclist on those they leave behind, including an emotional interview with his widow, Debbie.

Directed and edited by Laura Borner, the film, called White Bikes, also features an interviews with Mike Cavenett of the London Cycling Campaign, who talks about how cycle safety in the capital can be improved, and Mayor of London Boris Johnson's former transport adviser, Kulveer Ranger.

The latter was at the centre of controversy during the London Mayoral election earlier this year when Labour Candidate Ken Livingstone repeatedly asked Mr Johnson whether it was true that Mr Ranger had said that the mayor's prioritising of traffic flow took precedence over implementing measures that could improve the safety of vulnerable road users such as cyclists and pedestrians.

Concerns about the safety of cyclists had been raised in a report produced by consultancy Jacobs ahead of the installation of the Barclays Cycle Superhighway that Mr Dorling had been riding on at the time of his death, and that report is also discussed in the film.

Comments by Alexandra Goodship of Transport for London that ensuring traffic flows smoothly is in everyone's interests - including cyclists - suggests that the lessons from the death of Mr Dorling and other cylists, including Svitlana Tereschenko who died at the same junction a fortnight later, have not yet been absorbed by those who make the decisions.

Towards the end of the film, new measures at Bow Roundabout including a kerbed cycle lane and cyclist-only traffic lights are featured, but it's clear that the latter in particular creates a new hazard that did not exist before, with cyclists possibly believing the signal gives them right of way, which would place them in the path of traffic coming from the right.