Biker Gang Bloodshed

We well remember the Branch Davidian massacre near Waco. Now, biker gangs have shed blood in that same city. I can not conceive of why, if trouble was expected, law enforcement did not use magnetometers and pat-downs to disarm potential troublemakers. The shootout almost sounds like a Hollywood concoction, but with nine dead bikers, the gunfight was all too real. There is plenty of fault to go around, starting with the criminals who opened fire, but could RICO statutes not be employed to restrict outlaw motorcycle gangs? I also wonder how many of the casualties were from police gunfire as lawmen tried to take control of the situation.