If you want to get away with a lie, just drink a ton of water, wait a little while, and resist the urge to use the bathroom.

According to a new study at Cal State Fullerton, people are better at lying when they have to pee. Researchers had one group of people drink five glasses of water, then wait 45 minutes for their bladders to fill up. Another group only drank five sips.

Then both groups had to lie on camera about something they really believed, and also give one truthful statement. Then people watched the footage, and had to decide which statement was true and which was false.

It turned out the people who had to pee were MUCH better liars. The lies they told were more complex, more convincing, and they didn’t give off as many body language cues to tip people off that they were lying.

They think it has to do with something called the “inhibitory spillover effect.” Basically, our brains are wired to tell the truth, because it’s easier. But when you lie, you have to suppress that urge.

If you’re already suppressing another urge — like having to pee — it’s easier to do.