Here in Colorado, courts use the standard of "best interests of the child" when making decisions regarding what sort of child custody arrangement to establish when it comes to a child whose parents are getting divorced or splitting up. There are many different things a court may end up factoring in when deciding what would be in a child's best interests when it comes to child custody.
One is what wishes the child has expressed regarding child custody. As a note though, here in Colorado, not every child is eligible to have wishes they express regarding child custody considered by the court in a child custody case. This is because, under state law, a court is only to include the child's wishes into their best interests analysis if the child meets a specific maturity threshold.
Colorado law does not set this maturity threshold at a certain age. Rather, a child meets the maturity threshold if they are found to be sufficiently mature that they are capable of forming an independent opinion regarding child custody issues.
This fairly flexible standard when it comes to maturity threshold illustrates a general point regarding child custody cases. This point is that many of the standards regarding child custody are rather flexible ones that give courts a fair amount of discretion. Thus, many different factors can be at play in a child custody case and developing strong and well-supported arguments can be very important for a divorcing parent when preparing for child custody proceedings here in Colorado.
Source: FindLaw, "Colorado Child Custody Laws," Accessed April 9, 2015