Honestly, I don't see how you can argue it at this point. There's no reason Josh Barnett shouldn't be in the UFC.
Don't get me wrong, Josh Barnett is an amoral, unrepentant drug abuser. He has three positive tests, single-handedly scuttled an entire promotion and, to quote myself, “has a legitimate claim as possibly the most disrespectful, cancerous athlete in any sport, ever.” None of that is an outlandish claim (Dana White backs it all up here).
What you can't say about Josh Barnett, though, is that he's a bad fighter.
On the contrary, he is quite good. He is unanimously ranked as a top-ten heavyweight (which is possibly the UFC's shallowest division outside the newly-minted 125-pounders) and is probably the third-best wrestler in the heavyweight division, behind only Cain Velasquez and Daniel Cormier.
That, really, is the only thing that matters to the UFC.
Is that a good thing? No. Is that morally right? No. Is it good for public relations? No.
But the UFC, just like every other sports organization in the world, does not care. Not even a little. To quote modern-day rock band The Killers, “this is the world that we live in.”
The sports world, tragically, is morally bankrupt. The bottom line is that the only thing that matters to the UFC and to the fighters is winning (primarily because it improves their own bottom line). The examples are numerous.
The UFC tried to keep Alistair Overeem attached to the UFC 146 main event long after his failed drug test. Zuffa gave Nate Marquardt a job in Strikeforce despite his history of failed drug tests and dirty fighting, which initially caused his ejection from the UFC. Tim Sylvia and Sean Sherk received title shots immediately after testing positive for steroids. Thiago Silva was in two different main-event fights after being suspended for a year for submitting a falsified urine sample to cover for his PED use, and he has since tested positive again.
Granted, Barnett's numerous failed tests make him a greater offender than any of these fighters. Still, unless you are expecting the UFC to completely clean house, it is unrealistic (and perhaps even unfair) to expect them to apply different standards to Josh Barnett than to all the other fighters that have a history of issues yet are still happily retained by the UFC.
This is not to criticize the UFC. MMA fighters are hit harder for PED infractions than baseball or football players by a substantial margin. Additionally, Zuffa is far less tolerant of serious criminal infractions than the NFL, NHL, MLB or NBA (compare how Strikeforce handled Brett Rogers to how the NFL handled Ben Roethlisberger).
All that said, the UFC has demonstrated time and again that it is willing to work with almost anybody, as long as they have the tools to win fights and aren't getting in legal trouble out of the cage. Barnett has never been a concern in either of these departments.
Now don't get me wrong. I would downright love it if the UFC started taking a hard line on fighters that have been caught using. Unfortunately, that is not the case.
The reality of the UFC is that they don't really care, as long as you show up on fight night at the proper weight. Again, this is not to criticize the UFC. It is just the nature of the sports industry these days.
With that in mind, there is just no real reason for Barnett to be refused entry into the UFC. Adding him to the UFC just adds another exciting player to an already-solid heavyweight division that has plenty of compelling matchups possible at the higher levels.
Even if the UFC does grow a larger conscience, Barnett should not be the first fighter to get the boot.