The police pull you over on the way home from a social gathering. You were breaking the speed limit by about five miles an hour, so you think it’s just a speeding ticket. You hope it’s a warning.

Then the officer asks you to get out of the car and do some field sobriety tests. You haven’t had any alcohol, though you had a few nonalcoholic drinks at the party. You stumble on one of the tests, though, and the officer decides to bring you in. When they do a breath test, it comes back with a positive result.

How could this possibly have happened? You insist that you did not drink alcohol and drive, but the officers have the numbers right there in their favor.

It could be that someone spiked your drink without your knowing about it. This happens for various reasons. For instance, friends tend to do it most often to men, suggesting that they see it as a prank or a joke. Strangers tend to do it more often to women, suggesting that they may have something malicious in mind, and spiking the drink is just the first step.

But wouldn’t you notice? It’s hard to say. It depends on far too many factors. For instance, when did you drink that spiked drink? Maybe it was right before you left, so it hadn’t hit you when you got in the car. How often do you drink? Would you know the signs?

In any case, if you find yourself facing DUI charges as a result, you must know what options you have.