12:06 PM PT -- Jon says he never completed USADA anti-doping tutorials ... despite the fact he signed paperwork saying he did.

Jones says his management team took the tutorials for him and then forged his signature.

11:53 AM PT -- When asked about his use of sex enhancement supplements, Jones said, "I've had quite a bit of experience with Cialis and Viagra over the years."

11:49 AM PT -- Jones was asked what assurances he can give the commission that this won't happen again. Jones says he doesn't know how to answer the question because he didn't intentionally cheat in the first place.

Jones says, "My luck has been terrible when it comes to USADA."

11:48 AM PT -- Jon says he still wants to fight Daniel Cormier again. "I want to get that belt from Cormier."

11:44 AM PT -- "I've really tried everything in my power to get my life together."

Jon also says he's not a "screw up" and understands he's a role model for kids. He says he might be a knucklehead, but he's NOT a cheater.

11:41 AM PT -- "I have no clue how this happened."

11:40 AM PT -- Jon says he thought about who could have intentionally contaminated his supplements ... suggesting an enemy may have tried to take him down.

11:38 AM PT -- Jon says his nutritionist worked hard to make sure everything he took was clean and USADA approved.

11:34 AM PT -- Jon is testifying. He says he was very confused by the positive steroid test. Says he had to take a close look at the people around him to see if anyone would have contaminated his workout supplements.

10:24 AM PT -- Jon's attorney says the UFC fighter is not fighting the positive test, but he thinks the heavy $200,000 fine and revocation of his license is too harsh of a penalty.

Jon's attorney said, "He did not knowingly take the substance. He does not know where it came from."

The revocation would essentially last 1 year -- with Jones being able to reapply after 1 year has passed. The CA Athletic Commission would then decide to continue the suspension for another year or lift it.

Jon Jones is about to find out if he'll be SUSPENDED from fighting in the state of California over a failed UFC 214 steroid test.

He's about to face the California State Athletic Commission ... and we're livestreaming the whole thing.

TMZ Sports broke the news ... Jones tested positive for the anabolic steroid Turinabol in a test administered in July -- the day before he beat Daniel Cormier in Anaheim to reclaim the UFC light heavyweight championship.

Of course, Jones was stripped of his title -- and now he's facing up to $200,000 in fines (40% of his fight purse) and a possible suspension from the CSAC.

If the CSAC suspends Jones' license, he can't reapply until one year has passed from the date of revocation.

Jones is also facing punishment from another agency -- USADA -- which could hit him with a possible 4-year suspension. Jones is expected to meet with USADA later this year. There's no guarantee USADA's punishment will match the CSAC punishment.

The complication for Jones ... this is his 2nd offense. He tested positive for 2 banned substances prior to UFC 200 in Las Vegas in 2016 ... resulting in a 1-year suspension from USADA and the Nevada State Athletic Commission.