It all started with AB trying to point out the NFL's inconsistency when it comes to the way different players are treated in the wake of negative allegations.

Brown alludes to his former Pittsburgh Steelers teammate, Anthony Chickillo -- who was arrested this year for allegedly attacking his girlfriend.

Chickillo (who is white) was placed on the Commissioner's Exempt List and missed 2 games -- but was allowed to rejoin the team once prosecutors decided to drop the case.

The NFL is still actively investigating -- and Chickillo could face discipline in the future, but for now he's active and playing ... and AB is upset.

"Guess all mighty @nfl can hold players out against there will no criminal charges pending nothing but A Caucasian player gets a domestic go to jail still out there playing targeted hate against us everywhere my peeps."

Of course, Brown hasn't played since Week 2 as the NFL investigates rape allegations made by his former trainer, Britney Taylor.

The flaw in Brown's comparison is AB is a free agent and teams can sign him if they want -- but so far, no one wants to take the risk.

During his Wednesday morning Twitter sesh, Brown also addressed Ben Roethlisberger -- retweeting two people who brought up Ben's sexual assault cases.

AB didn't comment specifically on Ben's legal issues but did engage one critic who wrote, "Ab a real loser. Big Ben made that bum. Soon as Ben was done with him he was out the league."

Brown replied, "Check his stats before I came n I was done with that loser long time ago."

Yeesh.

When another person suggested AB should join the XFL, the WR shot that down hard too.

"No way," Brown wrote ... "they run the media they set me up clowns."