Any check is better than no check. But people are very good at selling themselves. They can say one thing and have intentions you do not suspect. For instance, they may agree to rules about dogs, loud music, working bees, but in the back of their mind know that once they're in, they will do whatever they like—build a meth lab, perhaps. This happened to a friend by the way.
I have heard enough stories to fill five books about people who were "ideal candidates" but ended up being nightmare neighbors, refusing to leave, turning into squatters. I know people who are dealing with such issues at the very moment. It is not easy. You want to be optimistic and believe in people, but reality says otherwise, again and again.
The best check you can have is a probation period, preferably a long one. Over the course of a year, you can start to get a sense of what someone is made of.
But even so, there is no way to ensure yourself against bad surprises. People change partners. They have children. Children become teenagers who do not embrace their parents' values. And on and on.
In my experience, the communities that work the best are those with an ideological or spiritual component: for instance, people with the same Guru or Christian or Buddhist faith. This spiritual or ideological component acts as a glue, a "greater purpose" that brings people together, gives them a certain discipline and reasons to respect the group.
Of course this is only an observation—I'm not saying it's a solution for everyone. But it raises question: What will be our "glue"? What is it that will prevent us from getting at one another's throats in hard times?
A friend who has been trying to convert his large organic farm to a community told me that a couple who were on his place for a test period and were asked to leave have put locks on one of his dwellings and have gone to the police claiming that they were tenants, even though they had never paid him a dime. It's not simple.
Some people are really good at reading others. Maybe someone on your committee has this gift. If not, it's not a bad idea, if it can be organized, to take your candidate to a market or a neighboring community and to gather impressions from people you trust.
Other than that, maybe you can convince the dad in Meet the Parents to lend you his lie detector.