The father of the child (the non-custodial parent) has a right to challenge any decision made by the custody evaluator. The evaluation should include all relevant factors, such as:
a history and reputation of mental illness or other problem; drug or alcohol problems; criminal records; physical or sexual abuse in the current relationship (including spousal abuse); and information about use of violence against women, children, pets and property during this marriage.
Each attorney will have different criteria for deciding whether to challenge an evaluation based on these factors. In general though, one easy way to determine if you need a lawyer is when you realize that your spouse’s lawyer wants nothing less than total victory from their divorce case(s). A good working relationship with an experienced family law attorney can often lead to them taking what would otherwise be a hostile approach toward your situation so they can get more money out of it later on down the road.