Advance Health Directive vs Will in Western Australia

They Solve Different Problems at Different Times

People often assume their Will covers everything — their property, their finances, and their medical care. It doesn't. A Will only takes effect after you die. An Advance Health Directive (AHD) takes effect while you're still alive but unable to make your own medical decisions.

That distinction matters enormously in Western Australia, where the Guardianship and Administration Act 1990 creates a strict separation between documents that govern your healthcare and documents that govern your estate. Confusing the two can leave your family scrambling to get legal authority during a medical crisis, when every hour counts.

What Each Document Actually Controls

A Will deals exclusively with what happens after your death. It names an executor to manage your estate, specifies who inherits your assets, and can nominate a guardian for minor children. It has no legal standing while you're alive — no hospital in WA will consult your Will to determine whether you want CPR or mechanical ventilation.

An Advance Health Directive deals exclusively with medical treatment decisions made while you're alive but lack the capacity to speak for yourself. Under Part 9B of the Guardianship and Administration Act 1990, a valid AHD sits at the top of WA's statutory hierarchy of treatment decision-makers. It overrides the wishes of your family, your enduring guardian, and even your treating doctor (with narrow exceptions).

Here's the practical breakdown:

The Gap Between Them — and What Fills It

Neither document covers a critical middle zone: personal and lifestyle decisions made while you're alive but incapacitated. Things like where you'll live, what support services you receive, and who manages your day-to-day welfare fall outside both your Will and your AHD.

In Western Australia, that gap is filled by two additional instruments:

• Enduring Power of Guardianship (EPG): Appoints someone to make personal and lifestyle decisions — including medical decisions not specifically covered by your AHD. The EPG only activates when you lose capacity.
• Enduring Power of Attorney (EPA): Appoints someone to manage your financial affairs and property. Can operate immediately or only upon incapacity, depending on how you set it up. Must be registered with Landgate if it involves real estate transactions.

The four documents work together as a complete framework. Your AHD handles specific treatment instructions. Your EPG handles the broader personal decisions your AHD doesn't address. Your EPA handles the money. Your Will handles what's left after you die.

Why You Can't Rely on Just One

Families in WA regularly discover these gaps during emergencies. A common scenario: a parent suffers a stroke and is admitted to hospital. The family has Dad's Will, but the Will is irrelevant — he's still alive. Without an AHD or EPG, the hospital turns to the statutory hierarchy of treatment decision-makers, which may elevate an estranged relative over a long-term partner or trusted child.

Another scenario: an elderly parent has an AHD specifying treatment preferences, but no EPA. The family needs to sell the parent's home to fund residential aged care. Without an EPA registered with Landgate, no one has legal authority to sign the property transfer. The family may need to apply to the State Administrative Tribunal for a formal administration order before the transaction can proceed.

The inverse also happens. A parent has a comprehensive EPA giving their eldest child full financial authority, but no AHD or EPG. The eldest child can manage bank accounts and sell property, but has zero legal standing to consent to or refuse medical treatment.

The Witnessing Rules Are Different Too

Both documents require witnessing, but the rules aren't identical in practice.

For an AHD in Western Australia, you need two independent adult witnesses. At least one must be authorised to witness statutory declarations under the Oaths, Affidavits and Statutory Declarations Act 2005 — this includes currently registered doctors, pharmacists, nurses, lawyers, JPs, and police officers. Retired professionals don't qualify.

A Will also requires two witnesses, but the legal requirements focus on a different set of restrictions: witnesses (and their spouses) cannot be beneficiaries under the Will, or they risk losing their inheritance.

The practical upshot is that you shouldn't assume the same two people can witness both documents without checking the specific rules for each one. A blog post on who can witness an advance health directive in WA covers the AHD witnessing requirements in detail.

Common Confusion Points

"My Will says I don't want to be kept on life support." That instruction has no legal force in WA. Your Will governs estate distribution after death. If you want to refuse life-sustaining treatment, that decision must be recorded in your AHD under Part 4 (Treatment Decisions).

"I've already appointed my daughter as executor — can't she make medical decisions?" No. An executor's authority only activates after you die and is limited to estate administration. For medical decisions during incapacity, you need an EPG appointing your daughter as your enduring guardian — or an AHD documenting your specific treatment wishes.

"Do I need to update both documents at the same time?" Not necessarily, but it's good practice to review them together. A significant health diagnosis might change your AHD treatment preferences without affecting your Will. Conversely, changes in family relationships (divorce, estrangement) might require updates to both your Will's beneficiaries and your EPG's appointed guardian.

Getting Both Right

The practical reality is that most Western Australians need at least three documents — an AHD, an EPG, and a Will — to be properly covered. An EPA becomes the fourth if you own property or have financial affairs that need managing during incapacity.

The Western Australia Advance Directive & Living Will Kit walks through the AHD and EPG side of this equation: completing the statutory forms, meeting WA's witnessing requirements, and uploading your documents to My Health Record so they're accessible during an emergency. The kit includes treatment decision worksheets and a signing checklist to help you avoid the procedural errors that invalidate documents.

Getting your advance care documents right while you're healthy means your family never has to argue with a hospital about what you would have wanted.

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