Happy 18th Birthday, New Adult

Ways the Law Affects New 18-Year-Olds

African female teenager blowing out the candles on her 18th birthday cake, surrounded by her family
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Eighteen is a magic birthday, a milestone into adulthood accompanied by great privileges as well as serious legal implications.

At 18, your teen can vote, buy a house or wed his high school sweetheart. He can also go to jail, get sued, gamble away his tuition via online poker, and make terrible stock market investments – just like you. That is because an 18-year-old is legally considered an adult in nearly every state in the union.

Here are five ways the law affects your new 18-year-old adult:


An 18-year-old cannot rent a car, but he can buy one. You may need to co-sign on the loan because he does not have a solid work or credit history yet.

He can also buy and sell real estate and stock, inherit property, enter into binding contracts, and, unfortunately, get sued.


Youthful legal misadventures that once might have netted parental wrath and a stern lecture from the local police can now land an 18-year-old in jail.

TP-ing the neighborhood or shoplifting may have landed them a slap on the wrist last week, but that is no longer the case. Even some minor drug possession charges that may have been overlooked at 17 can lead to some jail time at 18.

It is very important that your 18-year-old now understands their legal consequences, especially if they are still in high school and surrounded by younger friends.

Jury Duty, Taxes and Selective Service

In addition to voting, 18-year-olds are eligible for jury duty and they are responsible for paying their taxes on time.

Young men must also register with the National Selective Service. Failure to register could lead your teen to a $250,000 fine and/or five years in jail plus the loss of student loans and any federal or state employment. Need to register? Pick up a registration form at the post office or register online.

Driving Without Restriction

Some states have graduated driving laws that restrict the hours and terms under which new, young drivers can get behind the wheel. All driving restrictions are lifted at age 18.

Adults may chat on a hands-free cell phone, drive in the middle of the night and carry passengers.

Statutory Rape

Statutory rape laws are strange things. What is permissible in some states means jail time in others. Enforcement is unpredictable and the age of consent varies considerably from state to state.

In one case, a 17-year-old was sentenced to 10 years in state prison for having oral sex with a 15-year-old.

This is particularly important for 18-year-olds who may be dating someone younger than them, which often happens in high school.

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