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In family law, the term “custody” usually means decision-making. Having “custody”  means having the ultimate decision-making power over important decisions regarding the child, such as what child the school will attend, what religion the child will be raised in, what major recreational activities the child will take part in, and significant non-emergency health care decisions that need to be made for the child. Custody can be sole (where one parent has the sole authority to make major decisions), or it can be joint (where two parents share the decision-making responsibilities). It is important to differentiate between “joint custody” meaning decision-making, and “shared custody”, meaning two parents who share physical time with a child on a close-to-equal basis, which is not relevant when it comes to decision-making, but important when it comes to determining child support.

When we talk about “shared custody” for the purpose of determining child support, what we really mean is “shared physical custody”. In other words, how much time does the child spend with each of his or her parents? In Canada, we consider shared physical custody to be a situation wherein a parent has physical care of a child “not less than 40% of the time”. Family law lawyers sometimes refer to this as the “40% threshold”. It is only after a parent has crossed the 40% threshold that he or she can invoke section 9 of the Child Support Guidelines, wherein child support becomes more discretionary, and will be calculated by taking into account the income, means and needs of both parents, rather than just the “access” parent.

One confusing aspect of the shared-custody case-law is the fact that there is no universal formula for calculating the 40% threshold. In some cases, a parent may be over the 40% threshold if time with the child is calculated as a percentage of overnights, but that same parent may not be over the threshold if time is calculated based on the number of hours spent with the child.  Although there is no one correct answer to the question of how to calculate the 40% threshold, there are a number of rules and “themes” that have emerged in the case-law, which one can look to for guidance. Following is a summary of some of these rules / themes:

  • Parenting time is calculated over the course of a calendar year, not month by month. For example, summer is not looked at in isolation from the rest of the calendar year.
  • The onus of proving that the 40% threshold is met falls on the spouse seeking to invoke s. 9 of the Guidelines.
  • 40% is the minimum period of parenting time sufficient to trigger s. 9 of the Guidelines and Courts cannot just “round up” or “round down”.
  • The Court has the discretion and flexibility to count time in a way it deems appropriate in each family’s specific situation.
  • The two most common approaches to calculating the threshold are to count “days” and to count “hours”.
  • Although there is discretion, the weight of the authority in Ontario tends to support calculating the 40% threshold on an hourly
  • The relevant period of time to consider is the amount of time that the child is in the care and control of the parent, not just the amount of time the parent is physically present with the child. Time spent sleeping, in school or daycare, and in extra-curricular activities, will be allocated to one parent or the other.
  • It is common to start by crediting the custodial or primary parent with all the time the child spends sleeping and in school, except for those hours where the non-custodial / non-primary parent is actually exercising rights of access or has care and control over the child.
  • If a parent drops a child off at school and picks the child up after school it is usually reasonable to conclude that parent is responsible for the child over the course of that entire day.

If you know you are going to be facing an argument regarding shared custody and the 40% threshold, it is a good idea to keep a simple diary or calendar where you can note the days and times the child has been in your care. Although this may feel silly, or sad, it is often helpful to have a physical record in a situation where parties disagree regarding what has happened.

At the same time, it is also important to remain reasonable, and always consider the big picture. When a parent is over the 40% threshold, a judge still discretion to determine an amount of child support that he or she finds to be fair and appropriate in light of that particular family’s situation, including the income, means and needs of each party and the child. It is possible for a parent who has squeaked by the 40% threshold to still be ordered to pay the full Table amount, or an amount close thereto, especially if the other / primary parent is still bearing the majority of the financial burden in relation to the child, or has a much lower income. More often than not, once reaching the 40% threshold, parties will when negotiating default to the set off between their incomes to determine the child support, without considering the other factors in section 9, and this has become a practice but that is not always the right approach. For those interested, how to approach calculating child support under s. 9 of the Guidelines will be discussed in a further article.

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