donald joe barber, about to go on trial, and facing decades in prison. cast sovereignty in a heroic light. >> i can't do any less. >> reporter: but for bob powder, who lost his son, sovereign citizens are domestic terrorists who must be stopped. >> the pain is still there. it will always be there. but it certainly gives me satisfaction knowing that probably we're saving lives that some other family won't have to go through this. >> reporter: for "nightline," this is dan harris, in tampa, florida. >> our thanks to dan for that excellent report. >>> coming up, aliens sighted in the nevada desert. could it be true? we boldly go there, straight ahead. ♪ [ male announcer ] how could a luminous protein in jellyfish, impact life expectancy in the u.s., real estate in hong kong, and the optics industry in germany? at t. rowe price, we understand the connections of a complex, global economy. it's just one reason over 75% of our mutual funds beat their 10-year lipper average. t. rowe price. invest with confidence. request a prospectus or summary prospectus with in

we traveled to alabama, where we met donald joe barber, a pastor of a small church.in your view, do you need to have a driver's license? >> no. >> reporter: what about taxes? income tax? >> no. >> reporter: law enforcement officials fear that as barber and thousands of other sovereigns realize their theories don't fly, they will turn to violence. barber, however, insists his is a principled, peaceful struggle. >> just as a soldier goes over to iraq or to iran or any other country to fight a battle, he is going over there because he loves his country. i can't do any less. >> reporter: so, is that your view of what you're doing? >> yes. >> reporter: fighting for your country? >> yes. >> dan, what does law enforcement plan to do about this growing number? >> reporter: quite a bit now. the fbi said this is a top priority for them. and the southern law center, the group that issued the report. they made a dvd for local law enforcement officials that might encounter sovereign citizens. in the last year alone, they said they got 90,000 requests for that dvd from cops all ov