When the court makes decisions regarding parental responsibilities (custody), it may rely upon input from an neutral third party expert. There are various kinds of custody experts in Colorado: the CLR (Child Legal Representative), a CFI (Child Family Investigator), and a PRE (Parental Responsibilities Evaluator); CFIs are less expensive and state pay is available for low income parents, but the CFIs scope is also more limited than that of a PRE, which can be very expensive and which will include mental health testing of both parents.
The decision to request an expert of some kind depends upon many factors, but if you're legitimately concerned for your children's safety and welfare, you should discuss the option of hiring an expert with your counsel. Once appointed, experts can have a big impact on the outcome as they report directly to the court their findings and recommendations. .