No, even though the kid is tAll there is still a big danger risk. They should always be in a booster or carseat.
A child has to be four - six years of age before being able to ride without a booster. It is weight dependant and most booster seats will tell you the maximum weight or age on the packaging.
8 years old
10 years
they have to be 12 years old
If your talking about the booster seat without a back then NO, It is not safe for the child to ride with only a lap belt.
in all states a child has to be 4foot nine to be out of a booster seat. they can be in a booster sear at any age.
at age five
The Booster offers safe, comfortable rides for someones child. Moving from a car seat to a booster seat still helps the child remain safe, while riding comfortably in the booster seat.
In 15 years old
Different states have different regulations when it comes to how long children should ride in booster seats. Typically the average size and age is 4'9" tall and/or 8 to 10 years old. Check with your states guidelines to make sure your state's regulations are the same.
I belive the standard is the same in all states, and it goes by height and weight. I remember seeing those booster seat commercials and it was a rediculus heing like 4' 9" to ride without a booster, I would want to double check that answer though because it has been awhile since I have seen it.
All children under 8 years old are required to ride in a child safety seat or booster seat unless they are taller than 4 feet 9 inches.