The UK's Joanna Parker v The National Trust Judgment makes for interesting reading:

Parker v National Trust Judgment

Here, a crucial part of the evidence that supported The National Trust's defence was they had a tree risk management strategy* in place at Lyme Park, and carried it out.

Similarly, the National Tree Safety Group's (NTSG) 'Common Sense Risk Management of Trees', on which The National Trust's strategy was founded, looks like it was just as an important part of the evidence.

We wonder what the Judge in Cavanagh v Witley Parish Council might have made of that case if the experts had let him know the NTSG existed, and that they'd published, 'Common Sense Risk Management of Trees.'

Cavanagh v Witley Parish Council | A case of rough justice?

Here's a legal take on the Parker Judgment from Gabriel Fay at DWF LLP, that also explores its context in relation to the Cavanagh Judgment.

DWF | Joanna Parker v The National Trust

*Why's a Tree Risk-Benefit Management Strategy so important?

This paragraph, from an explanation of why the Tasmanian Government is adopting VALID's approach to tree risk, sums it up nicely.

"VALID is a complete Tree Risk-Benefit Management and Assessment system and not just another way of assessing tree risk. At its core is a Strategy that explains why and how the DSG is taking a reasonable, proportionate, and reasonably practicable approach to managing the risk from trees or branches falling. This establishes the context of any risk-benefit assessment. In the extremely unlikely event that a tree kills or injures someone on a state road, and there's a threat of legal or enforcement action, it's the Strategy that equips DSG with robust lines of defence about how they managed the risk."

DSG Tree Risk Upgrade