In Connecticut, operating a motor vehicle while under the influence of alcohol and/or drugs is a criminal offense. This offense may be prosecuted with or without any direct evidence of a person's BAC. The determining factor is whether a person's ability to drive has been impaired.
There are many other drugs that can affect a person's ability to drive safely. These drugs can have effects like those of alcohol, or even worse. This is true of many prescription drugs, and even many over-the-counter drugs.