"What's being done to filter out the criminal elements before they ship them up here to Texas?"
I would not worry about that too much. Texas isn't New Orleans. I have lived in Texas 26 years. One thing that has taught me is that Texans are willing to give most anyone a chance -- and are probably tougher than any other folks in the nation when it comes to slapping down those that abuse the chance they are given. We will be really nice to the honest folk that came here needing help -- and really hard on the criminals that think generous equals soft.
It was just reported that some of the Superdome crowd is now at the Dallas Convention Center---and guns were confiscated. I passed the Convention Center and Reunion Arena on the way home and both are literally surrounded by police vehicles. At least Dallas cops won't wait to shoot if they need to.