dallas police reporter: in dallas a domestic violence call officers on the scene. a carefully staged scene. it is our responsibility to investigate as much as we can. reporter: designed to teach the recruits the delicate nature of domestic violence incidents. maybe sometimes they feel like there is nowhere to go reporter: police departments nationwide may have domestic violence units in dallas all prolice recruits get special training and handling these incidents. this year almost 20% of the murder has been some sort of family violence related. reporter: dpd fields close to 15,000 domestic violence calls a year often repeat offenders. with victims who can be terrified to speak up so officers are trained to look for repeat violence. make sure you re okay. reporter: scan for injuries that may be hidden. how would you