If you don't trust your kids you don't let them go out on their own.
However, if your kids have not done anything to cause distrust, you ask them where they are going and to please check in every once in awhile. Then have them tell you about what they did when they get home.
If you are spying on them or being overprotective they will distrust you and it will cause a rift in your relationship. They will eventually leave home and this is the time for them to practice responsibility.