"Scientists examine behaviors such as drug use, violence, and participation in gangs in a paradigm of risk and protective factors. Risk factors, such as aggressive behavior and having friends who use drugs, can increase a person's chance for risky behaviors, while protective factors, such as secure family and community environments, can reduce the risk. Risk and protective factors exist on individual, family, peer, school, and community levels. Researchers stress that it is the accumulation of protective factors that have the most positive effect on teens in the long run in protecting against drug use or violent behavior. This report examines the relationship of teen drug use and violence and the risk and protective factors that parents and communities can take to keep their teens safe and drug-free. Teens who use drugs are more likely to engage in violent behavior, steal, use other drugs, and join gangs. In the past year, youth who used an illicit drug were almost twice as likely to have engaged in a violent behavior as those who did not use an illicit drug. And one in four teens (27%) who abused illicit drugs in the past year report attacking others with the intent to harm. Methamphetamine, marijuana, and prescription pain relievers are among the most abused drugs by teens who acted violently. The more drugs a teenager uses, the greater the tendency to engage in violent behavior."