A more thorough explanation:

The National Motor Vehicle Theft Act is also known as the Dyer Act. This law was passed in 1919 and made it a federal crime to transport a stolen vehicle across state lines. The purpose of this law was to help combat the rising problem of car theft and interstate transportation of stolen vehicles.

For example, if someone stole a car in New York and drove it to New Jersey, they could be prosecuted under the Dyer Act for transporting a stolen vehicle across state lines.

The National Motor Vehicle Theft Act was an important step in addressing the issue of car theft, as it allowed federal law enforcement agencies to get involved in cases that crossed state lines. This helped to make it more difficult for car thieves to operate and increased the chances of recovering stolen vehicles.