If it's affexting the workplace, then you probably can. It's like sending someone home if they're sick, so as not to make the other employees sick, you know what I mean? I think you should probably hold a small work meeting and talk about hte situation as a general thing.
Something like "I've started to notice that the attitude around here has gotten less than desireable, So I'm going to say this; If any one of you is here with a bad attitude, adn it's bringing the other employees down, I will make the decision to send you home for the rest of your shift. I understand that everyone has their bad days, but you need to deal with it in a more productive matter. Be in a bad mood all you want, but I'm not going to pay for it to affect my workplace. That being said, you know where I stand now, and if I send you home, you will not be paid for it. Hopefully it won't have to happen"
Kind of a short speech, but it gets the point across. Obviously, if you want to add or omit something, it's all on you. But maybe holding a quick staff meeting about it could fix the problem before you need to go to such measures. But if you must, be sure to follow through.
Good luck.
