Grounds for Full Custody of Child | How to Stop Risky or Unstable Parenting
15/07/2025
For some parents, the idea of seeking full custody arises from a slow build-up of worry, missed school pickups, erratic behaviour, or a co-parent who disappears for weeks without explanation. For others, the need arrives all at once, triggered by a crisis, an act of violence, or a moment of fear that changes everything.
Before taking legal steps, most parents want to know one thing: Do I have valid grounds? This is not a question to take lightly. Australian courts do not grant full custody based on emotional pain or frustration alone. They require evidence that one parent is unable, or unwilling, to meet the child’s needs in a safe, stable, and consistent way.
This article is designed to help you evaluate your situation through the lens of the law. You will find guidance on what courts consider legitimate reasons for awarding full custody, the types of evidence that support your claims, and what signs might suggest you have a strong case. Understanding these factors can give you clarity during a deeply uncertain time and prepare you to take the right next steps.
What the Law Actually Means by ‘Full Custody’
The term “full custody” is commonly used, but it does not appear in Australian legislation. In legal terms, the Family Law Act 1975 refers instead to parental decision making and living arrangements. Understanding these distinctions is essential before assessing whether your circumstances qualify for full custody.
Sole decision making means one parent has the exclusive right to make major decisions about the child’s upbringing. This includes education, healthcare and relocation. In contrast, shared decision making requires both parents to agree on these matters. Courts only grant sole decision making when it is clear that shared decision-making would not be in the child’s best interests.
Separately, courts decide on who the child lives with and how much time they spend with the other parent. In a full custody arrangement, the child typically lives with one parent full-time, and the other parent may have limited, supervised, or no contact, depending on the situation.
To clarify common misunderstandings, the table below outlines how the legal system defines “full custody” compared to how the term is often used informally:
| Common Understanding | Legal Definition in Australia |
| Full control over the child | Sole decision making |
| Child lives only with one parent | Child’s primary residence with that parent |
| Other parent loses all rights | Contact may be limited but not removed |
| No further involvement | Only in cases of proven and ongoing risk |
Clarifying this legal foundation is important. Full custody does not mean eliminating the other parent from the child’s life unless there is strong evidence that continued contact would cause harm. The next step is understanding what courts accept as legal justification for granting this kind of responsibility to one parent alone.
Legal Grounds for Full Custody
Courts in Australia do not award full custody based on preference, anger, or personal conflict. Instead, they look for clear and compelling reasons why one parent should hold sole decision making and primary care. These reasons must show that shared parenting would expose the child to harm or significant instability.
Below are the most recognised legal grounds for full custody:
- Family Violence or Abuse
If there is a history of physical, emotional, or psychological abuse toward the child or the other parent, courts will prioritise protection. This includes direct harm or patterns of intimidation and control. Even a single serious incident may be enough if supported by police reports, intervention orders, or professional statements.
- Neglect of Basic Needs
A parent who fails to provide consistent food, shelter, supervision, hygiene, or medical care may be found incapable of fulfilling their parental role. Courts assess whether neglect is ongoing and how it impacts the child’s health or development.
- Substance Abuse
Repeated or unmanaged alcohol or drug use that compromises parenting capacity is a major concern. This includes exposure to dangerous environments, unpredictable behaviour, or impaired judgement. Courts often rely on evidence such as treatment records, criminal charges, or witness accounts.
- Mental Illness Affecting Parenting Ability
Not all mental health conditions are disqualifying, but severe, untreated, or poorly managed illnesses that prevent a parent from safely caring for the child may justify full custody. Judges consider medical records, psychologist reports, and evidence of how the illness impacts daily parenting.
- Abandonment or Chronic Absence
If a parent has been consistently absent, physically, emotionally, or financially, the court may decide they have abdicated their role. This is particularly relevant when there has been no meaningful contact for an extended period without good reason.
- High-Conflict or Disruptive Co-Parenting
Some cases involve one parent who consistently undermines the other’s role, refuses to comply with orders, or creates an unstable environment through conflict. If this behaviour affects the child’s emotional security, it may support an application for full custody.
Each of these grounds must be supported with credible evidence. Courts do not assume harm, they require documentation, pattern recognition, and an understanding of how these issues affect the child’s day-to-day life. Once these grounds are identified, the court moves to evaluate them through the lens of the child’s best interests.
How the Court Evaluates the Situation
Even when serious concerns are present, the court does not grant full custody automatically. Every case is filtered through a central legal standard: the best interests of the child. This principle, outlined in Section 60CC of the Family Law Act 1975, guides all parenting decisions made by the Federal Circuit and Family Court of Australia.
The court will consider the following:
- What arrangements promote the safety of the child and the parents;
- The views expressed by the child;
- The developmental, psychological, emotional and cultural needs of the child;
- The capacity of each parent to provide for the child’s needs;
- The benefit to the child of having a relationship with the parents;
- anything else that may be relevant to the particular circumstances of the child.
In addition to the above general considerations, the Court will also consider if there is a history of family violence, abuse or neglect involving the child and if there is a family violence order that applies to the child or a member of the child’s family.
The Court will also consider a child’s right to enjoy their Aboriginal or Torres Strait Islander culture and the likely impact any proposed parenting order may have on that right.
These elements are applied on a case-by-case basis. No single factor outweighs all others. If you are considering full custody, it is essential to examine how your situation aligns with these standards. The presence of recognised grounds is one part of the equation, the other is showing how those grounds affect the child’s present and future wellbeing.
Signs You Might Have a Strong Case
Recognising potential grounds for full custody is the first step. The next is evaluating whether your situation reflects a pattern that courts take seriously. While every case is different, certain warning signs often indicate that sole decision making may be appropriate.
The checklist below is designed to help you reflect on your own experience. Answering “yes” to more than one of these questions suggests that your case may require urgent legal attention:
| Question | Yes | No |
| Has your child witnessed or experienced violence, threats, or controlling behaviour from the other parent? | ||
| Has the other parent repeatedly failed to provide basic care or maintain a safe living environment? | ||
| Is there a history of substance misuse that affects the other parent’s ability to supervise or support your child? | ||
| Has the other parent been absent for long periods with little or no contact or financial support? | ||
| Do shared parenting arrangements create constant conflict, stress, or disruption for your child? | ||
| Have professionals such as teachers, doctors, or counsellors raised concerns about your child’s wellbeing? | ||
| Have there been any police reports, intervention orders, or child safety notifications involving the other parent? |
These questions are not designed to replace legal advice, but to offer a clearer lens on your situation. Courts rely on facts and patterns, not assumptions or feelings.
When to Seek Legal Advice and What Happens Next
Understanding the legal grounds for full custody is a powerful first step, but knowledge alone will not protect a child from harm or resolve ongoing disputes. If you believe your situation meets the threshold for full custody, the next step is to take action through the proper legal channels, with the support of an experienced family lawyer.
It is best to seek legal advice early, even if you are unsure about pursuing court proceedings. A family lawyer can assess the strength of your case, explain your options, and help you prepare the necessary documentation. This includes drafting affidavits, compiling evidence, and managing interactions with the other party. If urgent protection is required, your lawyer can also help apply for interim orders to safeguard the child while the case progresses.
In more complex situations, the court may appoint a Family Consultant to prepare a report or recommend an Independent Children’s Lawyer. These professionals help the court form an objective view of what arrangement will serve the child best. Your legal team can assist you in navigating these stages and ensure your child’s needs remain the focus.
If you are concerned for your child’s safety or wellbeing and want to understand your legal position, we invite you to contact Cairns Divorce Lawyers. Our team is here to help you evaluate your case, guide you through the legal process, and protect what matters most.