Nearly a quarter of teens — 23% — admit to driving under the influence of alcohol, marijuana or prescription drugs used illegally at some point, a new survey finds.

What's worse, they don't view themselves as a danger: Almost 20% of those who drink and drive say it improves their driving, a view shared by 34% of those who drive under the influence of marijuana.

Those are among findings of a new survey of 1,708 11th- and 12th-graders by SADD (Students Against Destructive Decisions) and insurer Liberty Mutual.

The survey highlights the vital role of parents in keeping teens safe behind the wheel. It found that teens are more likely to drink around relatively unsupervised events, such as the Fourth of July or during the summer, than during heavily supervised activities like proms or graduations.

About twice as many teens report drinking on summer vacation than teens who admit drinking after prom or graduation, the survey found.

Cathy Chase of Advocates for Highway and Auto Safety says the percentage of teens who think they can drive safely after drinking or using marijuana "seems high. But unfortunately, it's not surprising because teens think they're invincible and they thing nothing will happen to them. Unfortunately, sometimes it takes a friend or someone in their school getting killed before the reality kind of hits them."

Source: USA Today
http://www.usatoday.com/story/news/nation/2013/04/25/teens-drunken-driving-impaired-survey/2106325/