City Hall has published some of the transcripts of interviews carried out by Dame Margaret Hodge during her probe of the Garden Bridge project.
The transcripts have been published under the Environmental Information Regulations, after requests from the SE1 website and others, including Conservative London Assembly member Andrew Boff.
The Mayor dropped his backing for the bridge at the end of April and the Garden Bridge Trust announced it was shutting down in August.
Here are some of the new insights from the first batch of transcripts:
The bridge's backers have always insisted that the river crossing would meet pressing transport needs, justifying millions of pounds from both Transport for London and the Department for Transport.
Transport for London commissioner Mike Brown told Dame Margaret that "...if I'm being honest where from a TfL perspective it's not overtly a transport imperative" and the Garden Bridge would not feature in his top 100 list of transport priorities for the capital.
Brown's candid comments to Dame Margaret contrast strongly with his previous public statements on the subject.
On 17 December 2015, Brown told the GLA Oversight Committee that he was "convinced that there is a very valid, legitimate transport imperative around this project".
Coin Street Community Builders chair Scott Rice told Dame Margaret that the Garden Bridge Trust had not responded adequately to concerns raised during negotiations over the South Bank land required for the bridge's southern landing.
Dr Rice said that Coin Street's concerns had been "filibustered", before going on to describe "a particularly tense moment with Mervyn [Lord Davies, GBT chair] ... where I was up against a lift outside of the meeting and there was a bit of finger-waving, saying 'Well, if this project goes down, we'll put the blame at Coin Street and you can imagine what that's going to be like in the Evening Standard'."
Joanna Lumley told Dame Margaret that if her original 1998 idea for a garden bridge as a memorial to Diana, Princess of Wales, had gone ahead, fundraising would have proved much easier.
She said" "I had to raise money for it and I wanted to use the name Diana because it was going to be called the Diana Bridge. The Diana Memorial Trust said I may not use her name in raising the money for this bridge. So that was a bit of a bummer because I could have raised the money in two dinners in America and the lottery."
Joanna Lumley: "We went along and the Mayor had asked us to look at a site between Battersea and Pimlico. So we went down there, dutifully, and looked at it and there was not one single human being there.
"I said if we were going to put a bridge there it would be just a complete waste of time. Nobody needed from Pimlico to go to Nine Elms or vice versa. There were no shops in Pimlico. There was no reason for a crossing there. A cycle path perhaps but not a pedestrian bridge."
Marks Barfield, creators of the London Eye, were one of three practices – along with Heatherwick Studio and WilkinsonEyre, invited to take part in TfL's hastily arranged procurement process for a bridge between Temple and the South Bank.
"The whole thing smelt wrong from the beginning," Julia Barfield told Dame Margaret.
David Marks went on to explain his anger that his firm's involvement in the process was used to put a positive spin on the project.
He said: "... I was really annoyed at the time because not only the former mayor, but the commissioner for TfL, was bandying our name around and using it to justify the fact that this whole tender process was fair and unbiased".
Ms Barfield described the incident as "a kind of bullying".
Thomas Heatherwick told Dame Margaret that he was contacted by a City Hall official, Justine Simons – then head of culture under Boris Johnson and now one of Sadiq Khan's deputies – after the 2012 Olympic Games, trawling for new ideas for London.
Heatherwick claims he was unaware that at this point Joanna Lumley had already written to the Mayor introducing the Garden Bridge concept.
As originator of the bridge concept, Joanna Lumley told Dame Margaret that she only made a few specific requests when the design was developed: "All I'd ever said to Thomas [Heatherwick] is that the two pillars, mustn't from the air look like a bra or a pair of glasses, ie it mustn't look seductive.
"It must be slim and beautifully done and also that you mustn't see it across.
"I had a third thing which they've taken no notice of, which is at Christmas it must have a Christmas tree on it."
Lumley told Dame Margaret: "We had this private donation from what we call the family, because they want to remain anonymous. And they had proposed, although they have now unproposed, £30 million. ... And they wanted to be anonymous but they felt that it would be a beautiful thing in London and they wanted to set up a bridge."
Joanna Lumley: "I'm anxious that Londoners, walkers particularly, people who can't afford a bicycle or a car, might not even be able to afford a bus fare, can walk across the bridge. A lot has been done for cyclists and nothing really has done for pedestrians except enormous patches for tourists.
"This is for Londoners. This is for Londoners and it's so strange, Dame Margaret, that something that I dreamed of almost calling the people's bridge, because it would be funded by the very rich for people who have nothing, for perpetuity, for people, has suddenly been turned round into the toffs bridge, and you go, 'Where did this happen?'
"So it's so odd and ... anyway, it doesn't matter. Whine, whine, whine. I've been told not to whine to you and I'm not going to but you suddenly feel the injustice and you go, 'This is the people's bridge for the people, a thing of utter beauty'."
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