Unfortunately, many people lie to the court during legal decision making (custody) and parenting time cases. Often, the person who is acting badly is the person lying to the court about the other parent. Too often, these people get away with it because the judge does not know who to believe.
One American soldier just solved this problem with his GoPro camera. His wife is accusing him of domestic violence while she is committing domestic violence against him. He hid his camera on his body and captured her not only committing domestic violence against him, but threatening to falsely accuse him of committing domestic violence against her. The story is here: http://www.wtsp.com/story/news/2015/09/20/soldier-uses-gopro-to-prove-wifes-domestic-abuse/72545676/
People often ask if it is legal to record telephone conversations and face-to-face meetings. People often tell me that they want to record the other party because the other party lies about what happens or what people say. In Arizona, it is legal to record a conversation of which you are a part. Therefore, you can legally record your phone conversations and encounters that you have with other people. You may not legally record the conversations of other people without their permission.
The story about the soldier who solved the he-said-she-said problem shows how to effectively use recording devices when the other parent lies to the court.