Car crashes are the number one cause of teen deaths in the United States, and 31 percent of teen drivers involved in fatal crashes were drinking alcohol at the time of their death, according to the National Highway Traffic Safety Administration. Despite decades of activism, teen drunk driving is still a big problem. So what can be done to help solve it?

Teen drivers may not be of legal drinking age, but that doesn't stop them from accessing alcoholic beverages. According to recent statistics from Students Against Drunk Driving (SADD), 72 percent of students have consumed alcohol by the end of high school, and the rate of binge drinking among those teens is as high as 17.4 percent. Some teens pay people they don't know to purchase alcohol for them, while others get it from unrelated adults or even from their parents, guardians or other adult family members.

Teen alcohol use often starts at a younger age than adults realize. One in three eighth graders drinks alcohol, and according to Mothers Against Drunk Driving (MADD), kids who start drinking young are seven times more likely to be in an alcohol-related crash.

While one in five teens admits to binge drinking, only one in 100 parents believe that their child engages in this kind of behavior. It's important for parents to talk to their kids about alcohol, and about drinking and driving, whether they think their teens are at risk or not. That's why SADD founded Parent Teen Matters, a website that helps parents start the conversation.

Parent Teen Matters encourages parents to talk openly about alcohol with their teenagers, set simple strategies like limiting overnights with friends and praise good choices. Parents can also connect with a local community coalition against teen drunk driving, and contact their state legislators to express their concerns and learn about any state laws that may address this issue.

Another important step parents can take is to know the parents or caregivers of their teens' friends. In a recent study, the American Medical Association (AMA) found that about 40 percent of teenagers reported easy access to alcohol from a friend's parents. Statistics like these have led many states to institute social hosting laws, which make parents liable for underage drinking. Parents who allow teenagers to drink alcohol in their homes can be fined thousands of dollars for each offense, and can be jailed if the teenagers are involved in an alcohol-related crash.

The AMA believes that teen drinking is a collective responsibility, and that laws like the minimum drinking age must be enacted and upheld in order to protect teenagers from the dangers of drunk driving. While there is some debate as to how effective these laws really are, with some experts arguing that the laws will push teens out into less safe environments in order to drink, research shows that restricting teen access to alcohol can help save lives.

Many states have zero tolerance laws for drivers under 21 who are found to have been drinking, arresting teen drivers with blood alcohol levels as low as 0.02 percent (the legal limit is 0.08). In Florida, for example, a first-time offender can expect to have their driver's license taken away for six months to a year. Teens that cause personal injury or property damage while driving under the influence can be jailed for up to one year. Florida's drunk driving laws also allow the victims of drunk driving accidents to sue restaurants, bars or hotels that knowingly serve alcohol to underage drinkers.

The key to preventing underage drunk driving may be a multi-pronged approach at school, through extracurricular activities, at home and through policy and community changes. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) outlines strategies for underage drinking that include reducing peer pressure through education at school, increasing supervision through after-school programs and strengthening family bonding.

Thankfully, teen drunk driving strategies appear to be paying off. A 2011 survey reported a historic decline in underage drinking in grades 8, 10 and 12. The Monitoring the Future survey conducted by the University of Michigan found that from 2006 to 2011, teen binge drinking dropped by up to five percent.

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