Joe the Plumber has a tax debt owed, not a lien.
A lien is when a debt is levied against an asset . . such as physical property or when the wages are garnished. A lien is farther down the road toward non-payment and is more serious.
I am aware of the difference, but I could swear the media reported it as a tax lien. But then....they frequently lie and often don’t do their homework well enough to know the difference.