One step is to have probation officer accompany police officers in police cars in the evenings and on weekends, or whenever juveniles are on the streets. The probation officers can question probationers on the street corners, enter their homes, monitor their school attendance, and question them about their drug involvement and their gang involvement. This increases the surveillance effectiveness of probation officers. A second step is for the police to put pressure on gangs. In Boston, for example, if a gang commits a violent crime, the authorities cooperate to bring pressure on the entire gang, making clear that the use of guns and other forms of violence will not be tolerated. A third step is to enforce truancy laws. This means making clear that school-aged children who are not at home, at work, or at school are not to be on the streets. Other tactics police can use to counter juvenile crime are random frequent drug tests, gun searches, and zero tolerance for misdemeanors.