In Unsworth v Hennessy [2024] NSWLEC 82, an ongoing tree dispute between neighbours in Mosman raised issues of statutory interpretation, jurisdiction and procedural fairness in the application of the Trees (Disputes Between Neighbours) Act 2006 (NSW).

Chief Justice Preston of the Land and Environment Court upheld the earlier decision of Acting Commissioner Galwey that a lilly pilly hedge presented an ongoing obstruction of sunlight and view, in favour of the applicant.

The behaviour of litigants in tree disputes is relevant to a determination of the matter, and not beyond scope of the decision maker to consider.

Key points

• Section 14D of the Trees Act grants the Court broad remedial powers to deal with tree disputes for severe obstructions of views or sunlight.
• The impact of trees on neighbouring properties is a matter of fact and degree depending upon the facts and circumstances in each particular case and the severity of these impacts needs to be determined on a case-by-case basis.

Background

This was a dispute involving two neighbours (Mrs Unsworth and Mrs Hennessy) and the height of a hedge of trees that ran along the common boundary of their properties in Mosman.

The subject hedge consisted of lilly pilly trees owned by Mrs Unsworth. The trees had grown to a height that obstructed Mrs Hennessy’s view to the west of her property, overlooking Mosman, Cremorne and Neutral Bay to the North Sydney Skyline.

In April 2023, Mrs Hennessy applied to the Court under section 14B of the Trees (Disputes Between Neighbours) Act 2006 (NSW) (Trees Act) for orders requiring Mrs Unsworth to prune and maintain the hedges at the height of the fence dividing the two properties.

In December 2023, Mrs Hennessy successfully obtained orders that Mrs Unsworth prune the hedge twice yearly to a height no greater that 150mm above the height of the fence (among other consequential orders). The Commissioner found that:

“[t]he respondent’s lilly pilly hedge severely obstructs a view from the applicant’s dwelling. Having balanced the interests of each party, I find that the hedge can be maintained at a height that will remove most of its obstruction of the view without adversely impacting the respondent’s privacy.”: at [52].

Mrs Unsworth appealed against this decision under s56A(1) of the Land and Environment Court Act 1979 (NSW). This appeal was limited to questions of law. Preston CJ summarised the issues at [10] to be determined as follows:

1. the Commissioner misinterpreted and misapplied s14E(2)(a)(ii) of the Trees Act by assessing the degree of obstruction of the view from Mrs Hennessy’s house not by the degree of obstruction of the trees of the hedge as they existed at the date of the hearing but instead by the degree of obstruction of the trees as they would be under the most likely state of affairs, being 200mm taller than the trees’ height on the day of the hearing;
2. the Commissioner misinterpreted and misapplied s14D(1) of the Trees Act by not limiting the order for pruning to only those trees of the hedge found to cause a severe obstruction of the view from Mrs Hennessy’s house but instead ordering pruning of all of the trees in the hedge; and
3. the Commissioner denied Mrs Unsworth procedural fairness by not giving her a reasonable opportunity to address the Commissioner’s assessment of the degree of obstruction of the view on the assumption of the trees being 200mm higher than they were on the day of the hearing.

These three issues were determined as follows:

The erroneous date of assessment issue

Preston CJ found that the Commissioner had not misinterpreted s14E(2)(a)(ii) of the Trees Act. Relevantly, section 14E(2)(a)(ii) provides that “the Court must not make as order under this Part unless it is satisfied that the trees concerned are severely obstructing a view from a dwelling situated on the applicant’s land”.

The Commissioner’s findings of the state of the trees and the obstruction as a consequence of the trees in the ongoing state of affairs were based on these two facts:

1. that the trees were 600mm above the fence when Mrs Hennessy filed the application (being 200mm taller than their height at the day of the hearing); and
2. Mrs. Unsworth stated that she intended to maintain them at that height of 600mm above the fence in future.

Although the trees were pruned to 400mm before the hearing, they still obstructed Mrs. Hennessy’s view significantly. The Commissioner determined that, absent further pruning, the trees would eventually return to their previous height of 600mm and similarly obstruct the view. This assessment led the Commissioner to conclude that the ongoing state of affairs would mirror the past state, where the trees formed a dense hedge severely blocking the view.

Mrs Unsworth argued that the proper interpretation of “obstructing” was that the Commissioner was bound to assess the height of the trees as they stood on the date of the hearing. Preston CJ described pruning trees in advance of the hearing as “opportunistic” [sic] at [12] and determined that “[o]n a proper construction, s 14E(2)(a) permits the assessment of the degree of obstruction of sunlight or a view as a consequence of the trees to be over a longer timescale” at [28].

Preston CJ was also of the view that this issue was a challenge against the factual findings of the Commissioner, rather than a matter of law. It was found that the Commissioner’s decision did not misinterpret the relevant law, and this ground of appeal was rejected. Based on this, Preston CJ also concluded that it was unnecessary to address the issue of the Commissioner’s interpretation of s14E(2)(a)(ii).

The erroneous order issue

Section 14D of the Trees Act provides:

14D Jurisdiction to make orders

(1) The Court may make such orders as it thinks fit to remedy, restrain or prevent the severe obstruction of:

(a) sunlight to a window of a dwelling situated on the applicant’s land, or
(b) any view from a dwelling situated on the applicant’s land,

if the obstruction occurs as a consequence of trees that are the subject of the application concerned.

Mrs Unsworth argued that an order to prune her hedge should be limited to only those trees that severely obstruct the view from Mrs Hennessy’s house. The hedge, consisting of about 20 trees, was found to obstruct views from specific windows in Mrs. Hennessy’s house. The Commissioner determined that the obstruction affected windows W3 and W4 most significantly but did not specify which trees were obstructing which windows. Mrs Unsworth contended that the order should only address trees causing severe obstruction and not extend to unaffected parts of the hedge.

Mrs Hennessy, on the other hand, argued that the order was justified for the entire hedge since the obstruction was linked to the group of trees, not individual ones.

The Preston CJ upheld the Commissioner’s decision, ruling that the order under s14D(1) could encompass all trees in the hedge if any were found to obstruct the view, reflecting the broad remedial scope of s14D(1).

The procedural fairness issue

Mrs Unsworth argued that the Commissioner denied her procedural fairness by failing to disclose the framework he used to assess tree obstruction, which was based on the anticipated future height of the trees. She contended that this lack of notice prevented her from adequately presenting evidence and arguments.

Mrs Hennessy contended that the Commissioner’s consideration of the ongoing state of the trees was a result of Mrs Unsworth's own actions, including recent pruning and a stated intention to allow the trees to grow back to their former height.

Preston CJ found that the Commissioner was not obligated to notify Mrs Unsworth of the specific interpretation of s14E(2)(a)(ii) before making his decision. Additionally, it was noted that Mrs Unsworth had ample opportunity to present evidence and make submissions regarding both the current and potential future heights of the trees. Preston CJ concluded that the Commissioner did not deny procedural fairness in his assessment.

Conclusion and orders

It was found that Mrs Unsworth had not established that the Commissioner erred on a question of law in any of the ways raised in the grounds of appeal. The appeal was dismissed, and Mrs Unsworth was ordered to pay Mrs Hennessy’s costs of the appeal.