As a first crude cut at it, it appears that Texan Hipanics are pretty law abiding.
As a long-time former resident of inner-city Houston (the Hispanic area), there is a certain amount of crime in these areas, just not as much as in the black inner-city neighborhoods.
But there is also a good respect for law and order, especially among the US Hispanic citizens, less so among the illegals, but there is still some there (maybe fear of the law). Also, everyone in the Hispanic barrio owns a gun (New Year's Eve sounds like the American army invading Berlin). And there is a strong amount of private development going on.
In fact, Dallas and Houston are really the only two Texas cities with any inner-city black population. Could explain part of the difference (without wanting to sound sort of racist)
That has been noted before. It's been suggested that Texas hispanics have a longer cultural presence in the state and feel part of the system. Or, that the more recent hispanic influx comes from a part of Mexico that is more law-abiding.
Whatever the reason, the hispanic presence in Texas doesn't equate to an increased level of violence and crime as seen in other states.
Of course, crimes are committed by people of all races in Texas so it's not hard to find exceptions to the rule, but your observation seems to be accurate.