Many criminal activities are regulated at the state level, including the punishments allotted for each given act. This is why a first-degree murder conviction might result in the death penalty in one state where the death penalty is legal, but the same crime would likely mean life in prison in a state where the death penalty is not legal. Some crimes, including many sex crimes, go beyond state laws and enter the realm of federal offenses.
Many of the most common sex crimes, such as sexual assault, child molestation and others, are handled at the state level, meaning that the state laws will determine the punishment. There are less common issues that are considered federal offenses, and these offenses usually occur when multiple states or countries are involved in the criminal act.
Some of the most notable examples of federal sexual offenses are interstate transportation with the intent of prostituting the transporting individual, interstate travel with the intent to have sexual relations with a child and producing sexually explicit depictions of children with the intent to import into the United States. There are many more federal offenses, but as you can see, each offense generally involves interstate or intercontinental transportation.
This means, for instance, that if you were accused of kidnapping a woman in Florida and traveling across the state border with the intent to sell that woman for prostitution in Alabama, it would likely be a federally prosecuted case. Federal cases bring their own complexities and penalties, so it is even more important to consult with an attorney if you are accused of a federal sex crime. Don't wait until the police are knocking at your door. Contact an attorney as soon as you realize you are a suspect.