Discreet Investigation Service

What is Cohabitation and How to Investigate it


Cohabitation is when two people in a romantic relationship live together under the same roof. This post will discuss the relevance of cohabitation, the proper way to prove cohabitation, and what does and does not constitute proof of cohabitation.

Many investigators do not fully understand what cohabitation is or how to prove cohabitation, so they fluff what they understand, costing clients a lot of time and money without positive results. We have even seen lawyers who do not fully understand what is involved in cohabitation, but having successfully completed so many cohabitation investigations ourselves over our 50-plus years of experience in the private investigation sector gives us a the understanding of cohabitation investigations required to deliver the results you need.

There are two ways to conduct a cohabitation investigation: the first, which is the most difficult and often impossible, is to show that both cohabitants are financially intertwined and both contributing to household expenses. The second way is easier and more successfully completed; this involves putting the residence under surveillance. Around-the-clock surveillance is unnecessary, but generally speaking we will establish surveillance between 4:00 a.m. and 5:00 a.m. and maintain it until somewhere between 10:00 a.m. and 12:00 p.m. The surveillance is carried out Monday through Friday for two weeks. (One week of surveillance can be performed instead of two, but two weeks is standard and three weeks is optimal). The idea is to document the coming and going of any cohabitants by monitoring their vehicles. Weekends are not as important as they are considered recreation time and do not hold much value in proving cohabitation.

Although the above paragraph defines the basic cohabitation investigation, there are many additional factors involved in order to to make sure what is being documented will cover all aspects of the case; for instance, do either of the cohabitants have another residence? Do either of the cohabitants possess multiple vehicles? Is the cohabitants’ relationship already established on paper or does it need to be proved? Etc. These are all issues an experienced and trained detective agency will guide you through in a cohabitation investigation.

It is important to be wary of inexperienced agencies that may guide you in the wrong direction in a cohabitation investigation. When looking to prove cohabitation, avoid the following misconceptions of what type of investigation is needed:

  • Pictures from the middle of the night of both vehicles together
  • Requiring both financial information as well as visual proof
  • Weekend surveillance
  • Around-the-clock surveillance
  • Statements from a friend saying a couple are living together
  • Less than one week of surveillance

By understanding what is truly needed to conduct a successful cohabitation investigation, you can avoid inexperienced detective work and make sure you are investing in gathering real results.