This reminds me of the ATF attack on the DK compund in Waco, Texas. The ATF/FBI could have easily have picked up DK with little, if any, resistance or danger during his daily run into town; but then again, that would have deprived the AFT, FBI, and other LEO of the oppurtunity to play with their expensive toys.
The same situation in Tucson. If the press can find out where the guy worked and what time his shift was over, they probably could hjave picked him up then without firing a shot.
They could have *easily* set up near his car while at work, and hooked him while walking to his car. At the same time they could have easily served a warrant on his residence.