Cohabitation

How Cohabitation Affects Child Support and Spousal Maintenance

What Happens to Child Support and Spousal Maintenance if You Cohabitate During or After Divorce?

Couples going through a divorce are often unclear as to what legal effect, if any, moving in with a new partner will have on their legal rights. Most commonly, there is a concern that cohabitation (living with a new boyfriend or girlfriend in a ‘marriage-like’ arrangement) might affect a spousal maintenance award or the amount of child support that is to be paid or received.

The following provides general information for individuals considering moving in with a new spouse or partner during or following a divorce—as well as those seeking to modify maintenance or child support based upon the cohabitation of a former spouse.

What is the Legal Effect of Cohabitation on Spousal Maintenance?

In general, in Washington State, a spousal maintenance award (sometimes called ‘alimony’) cannot be modified unless:

  • there has been a “substantial change in circumstances,”
  • that was not contemplated by the parties at the time of their divorce, and
  • that implicates the ability of one spouse to make their required payments or the financial need of the spouse receiving maintenance.

For example, if a spouse that has been ordered to pay spousal maintenance declares bankruptcy, loses a job or experiences a failure of a business, a court may consider the new financial situation to be a “substantial change in circumstances” and accordingly decrease the amount required to pay. Similarly, if a spouse entitled to receive maintenance wins the lottery, the decreased financial need will also probably result in a decrease or termination of the maintenance award.

Based upon Washington’s “substantial change in circumstances” rule, cohabitation (or even remarriage), by itself, does not justify the modification of a spousal maintenance. In fact, the termination of spousal maintenance based solely upon cohabitation is not permitted in Washington State.

However, if cohabitation results in significantly increased economic support (perhaps as a result of a new spouse’s income) and meaningfully reduces financial need, then a reduction or termination of alimony obligations might be justified. In the same way, if cohabitation results in a spouse’s substantially increased ability to pay, the monthly required payment may be increased.

What is the Legal Effect of Cohabitation on Child Support?

The rules concerning cohabitation and the modification of child support are similar to those governing the modification of spousal maintenance awards. Child support orders cannot be modified based upon a showing of cohabitation alone. However, if one spouse has experienced a “substantial change” in financial circumstances as a result of cohabitation, it is possible to petition the court for a modification of a child support order. Because of the way child support is calculated, however, it sometimes difficult to prove that cohabitation has resulted in a relevant “substantial change.”

Child support obligations are allocated between parents based on each parent’s share of their combined monthly net income. Thus, the income of a new non-parent spouse or partner (who is not legally obligated to care for or support the child at all) is generally not included in calculations of child support. As a result, even cohabitation with a very wealthy new spouse may be insufficient to justify a modification of child support.

Of course, that does not mean that the income of a new spouse is entirely irrelevant to a court’s decision. In fact, a number of Washington courts have chosen to grant a modification of a child support order based largely on the income of a party’s new spouse because it affects that party’s “economic prospects” (a factor that a court is permitted to consider when adjusting child support).

Thus, like spousal maintenance, cohabitation will not automatically or necessarily result in the modification of a child support order, but it may be considered by the court when determining whether a substantial change in circumstances has occurred.

Can a Couple Agree to Modify Child Support or Spousal Maintenance (Through a Pre-nuptial or Separation Agreement) Due to Cohabitation?

Child support, because it is determined by statute and based upon income, cannot be modified by private agreement. Any attempt to include a provision in a pre-nuptial or separation agreement limiting the payment of child support based upon cohabitation is ill advised and will not be enforceable in court.

Agreements to modify spousal maintenance upon cohabitation are more common. Some agreements and divorce decrees, in fact, explicitly list certain events (including cohabitation) that will trigger an automatic modification. If your decree or agreement includes such a provision, either spouse may petition the court for a modification of a maintenance award based upon one spouse’s choice to cohabitate. The outcome of that petition will likely depend upon an evidentiary hearing conducted by the court, and many Washington courts have found modification provisions triggered by cohabitation to be unenforceable. Thus, it is important to recognize that, in this arena, even a written agreement may not provide a guaranteed result.

An evidentiary hearing is not necessary if both parties can agree to a modification of spousal maintenance. An agreed upon modification can simply be drafted by the parties and submitted to a judge for approval.

When you believe proving cohabitation will result in reducing your alimony payment amount or prove a danger to the welfare of your child, below are 5 steps to prove cohabitation exists.

5 Steps to Prove Cohabitation

There could be any number of reasons why you need to prove cohabitation between your former spouse another person. Maybe your ex-spouse has a new partner moving in that may be a danger to your child’s welfare. Perhaps they are now living and being supported by their new partner – which means your alimony payments may be reduced, or even eliminated.

No matter the reason, private investigators know how to get the evidence you need to prove cohabitation – and possibly amend your divorce agreement.

More often than not, proving that your former spouse is cohabiting with someone that poses a threat to your child can result in an immediate amendment to your divorce agreement. However, proving cohabitation to reduce or terminate the payment of alimony can take a few weeks or a few months, depending on the state you reside.

To prove cohabitation and show that your ex partner is living with someone you’ll need:

  • Surveillance
  • Identification of individuals
  • Interviews of key people
  • Financial asset audits
  • Background checks

1. Surveillance

Surveillance is going to be your best friend throughout the investigation. You should hire a private investigator to avoid possible stalking charges if you were seen conducting surveillance yourself. By collecting evidence about where your ex spends the night (which is presumably with a partner), you can build the foundation of evidence for your case. When hiring a private investigator for this step, you can have them testify in court for you, further backing up your case.

Remember, each state has different standards when it comes to proof of cohabitation. Some states may require longer periods of surveillance. If you’ve hired a private investigator to stake out your former partner’s house, they should know how much proof is required and can use other techniques to speed up this process and provide multiple forms of evidence.

2. Identification of Individuals

This is relatively straightforward, but very important. Once your investigator has collected evidence that your ex-spouse has been staying overnight at a residence, or has someone spending the night with them, you’ll need to identify the person. This can take the form of photographs, records of vehicles visiting the residence, mail being delivered and other methods.

3. Interviews of key people

The next step is to have your investigator ask people that know your ex-spouse questions that could potentially lead a judge to believe they are cohabitating with someone. This includes reaching out to their neighbors, friends, coworkers, etc. They may back up your case or provide further leads for your investigator to contact and interview.

On its own, performing interviews isn’t going to be enough to prove cohabitation. But, if a friend lets slip that your ex-spouse has been living at that residence for the past two months, it can tip the scale in your favor.

4. Financial Asset Checks

By having a private investigator research the financial affairs of your former spouse’s new partner, you might be able to bring to light that your ex-spouse is staying at a residence that they own, or even co-own with another person. Just like performing interviews, this alone won’t prove cohabitation. But it can help to prove that your ex-spouse is residing with someone who potentially has the means to support them, which can be instrumental in reducing or terminating alimony.

5. Background Checks

The final step is to run a background check. This is best conducted by a private investigator, since they’ll know where to look to find the best information to support your case.

Background checks can discover a wealth of data. In the context of proving cohabitation to amend a divorce agreement, background checks can potentially show that your ex-spouse and their partner now have the same address, share their bills, or have cars registered to the same address. Coupled with the other techniques we’ve discussed, it may be enough for a judge to amend a divorce agreement.

Hopefully this post helped you understand how to prove cohabitation between your former spouse and their partner. If you’re having a hard time finding the right information, or if you need an investigator, we can help. For more information about how we can assist you, you are invited to contact Washington State Investigators and speak with our principal investigator today.


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