When you're in the thick of a negotiation, it can be hard to know whether the person on the other side of the table is trustworthy or not. Are they acting a little weird, you might think, or is it just paranoia? 

Here are three ways to know the difference. 

They talk way too much -- or far too little
A study on truth-telling in negotiations came up with a few quirky linguistic results that you might be able to apply to your own negotiation. 

Outright liars, or those who are saying something patently false, tend to use more words than truth-tellers. The authors describe it as the "Pinocchio Effect": as the lie grows, so do the number of words (just like Pinocchio's nose in the fairy tale). 

Liars also tend to use more complex sentences, maybe to absorb all the extra verbiage that they're packing in. 

On the other hand, people who are lying by omission -- that is, leaving out vital information rather than substituting it with false information -- tend to use fewer words than truth-tellers. They also use shorter sentences. Makes sense: attempting to keep specific information out is easier if you limit the total amount of information you're sharing.

Thus, be on the lookout for people who are incredibly verbose and for those who seem suspiciously terse. Your counter-party might just like to hear himself speak (or not), but there could also be a hidden reason for their language choices. 

They swear a lot or talk in the third person 
In the same study, the authors also noticed that liars tended to respond to suspicion by swearing. In other words, expressing a level of doubt about whether a liar is telling the truth can prompt them to start swearing. Why? The researchers suggest that it probably has something to do with the amount of effort it takes to lie -- after all, it's hard to keep control over every part of your brain at the same time. 

So, if you raise a doubt and the response is a bit of a potty mouth, you may have an explanation: it's possible that you've just stepped on the other person's lie. 

There's also a greater tendency by liars to use more third-person words (e.g., "he", "she", "it"). The authors point out that this might be a distancing technique -- even if someone is lying, he or she probably doesn't actually like to feel like a liar. 

They're talking to you at the wrong time of day 
Finally, a weird but useful technique is to ask whether the person you're dealing with is a night owl or a lark -- and make sure you aren't negotiating at the wrong time of day.

Why? A study on time of day preferences uncovered a weird fun fact: Morning people (or those who tend to wake early naturally and feel most alert in the morning) are more likely to cheat at night, and night people are more likely to cheat in the morning.

That implies that in a negotiation, it could be tempting to cheat if you're working at the wrong time of day. It might have something to do with tiredness and self-monitoring, but -- unlike the above cues to spotting a liar -- you can try to avoid it. 

For example, if you know for a fact that your counter-party goes running at 4 in the morning, maybe reconsider that dinner meeting to discuss your negotiation. Instead, go for breakfast -- it's not foolproof of course, but it could help set the groundwork for a more ethical negotiation.

Unless, of course, you are a night owl. In that case, maybe split the difference and go for lunch.