Justin Bieber's brawl with a photog over the weekend isn't going to just disappear ... TMZ has learned the case WILL be referred to the L.A. County D.A. for possible criminal prosecution.

We're told cops have already decided to refer the case to prosecutors, even though the investigation is far from complete.  They have requested to interview the Biebs, but he's in Norway now.  It's pretty typical for police to refer high-profile cases to prosecutors.

TMZ broke the story ... Bieber's a suspect for allegedly committing criminal battery against a photog in Calabasas Sunday afternoon. The photog called 911 after the scuffle, but by the time cops arrived, the singer had split.

The pap was taken to a nearby hospital in an ambulance. He then filed a police report naming Bieber as the culprit.

If Bieber is charged and convicted, he'd face 6 months in jail.  But the photog faces an even worse fate -- having to tell people Justin Bieber kicked his ass.

In an odd bit of foreshadowing, Justin Bieber hung out with Mike Tyson and got some boxing tips from the legendary fighter just days before his alleged run-in with a paparazzo.

Check out the Biebs working the heavy bag with Tyson. They posed for a pic with another guy, which Tyson tweeted with the caption, "Me, @johnny and @justinbieber before we started training JB"

As TMZ first reported, Bieber is now a suspect in a criminal battery after Bieber allegedly got into it with a photog in Calabasas. Cops were called to the scene -- Bieber and GF Selena Gomez had already split -- and the photog was transported to a nearby hospital and later released.

Witnesses say the pap incited Bieber and got tips from a lawyer at the scene about calling an ambulance and filing a police report.

Justin Bieber is a suspect in a criminal battery ... law enforcement sources tell TMZ.

Justin was in Calabasas, where he lives, just after noon Sunday at a mall called The Commons.  A paparazzo attempted to take Justin's picture and, according to law enforcement, some sort of physical altercation erupted between Justin and the camera guy.

The photog called 911, and when cops arrived Justin and GF Selena Gomez had already split. 

The photog complained of pain to his upper torso, an ambulance was summoned and he was taken to a local hospital where he was examined and released a short time later.

The photog filed a police report naming Justin as the culprit. Cops are investigating the incident as a misdemeanor battery.

Law enforcement tells us detectives want to speak with Justin, Selena and any other witnesses.

We placed a call to Justin's rep ... so far, no comment.


We're told several witnesses at the scene say after the altercation, a lawyer walked up to the photog and said he could get a lot of money out of the incident and advised the dude to call for an ambulance and file a police report. 

Witnesses also say the photog had been blocking Justin's car as the singer was trying to leave.  Justin got out of the car and asked the guy to move away but he wouldn't, and a scuffle ensued.

Justin Bieber thinks the folks behind the "Joustin Beaver" mobile app need a lesson in geography ... claiming they filed a lawsuit against him in the WRONG STATE and now he wants it dismissed ASAP.

Bieber has been going back and forth with a company called RC3 -- they claim their game is a parody and protected under the Constitution ... but Bieber feels the game infringes upon his likeness and wants it pulled ... STAT.

According to court docs filed this week, Bieber is looking to have the suit tossed on a technicality -- claiming RC3 screwed up when they filed their suit in Florida, since he doesn't even live there. 

We'll see if the move works ... a judge has yet to rule.

Looking like he wandered off the set of "Goodfellas," Justin Bieber rocked a golden diamond-encrusted fish around his neck at the Mayweather fight on Saturday -- and TMZ has learned, the thing cost $20,000!!!

Sources tell us, the 14k gold "koi" fish -- designed by celeb jeweler Ben Baller -- boasts 14 carats of VVS diamonds all over (supposedly fancier than normal non-VVS diamonds). Even the chain is covered in 12 carats of diamonds.

it's unclear if the necklace was a gift or if Bieber paid for it himself.

FYI -- Koi fish represent good luck. Not like Mayweather needed it.

Last year, they engaged in the best boxer-on-octogenarian fight ever ... but now legendary sportscaster Larry Merchant says he and Floyd Mayweather are "the best friends ever."

You'll remember ... Merchant and Mayweather really got into it during their post-fight interview last September ... when Merchant famously screamed, "I wish I was 50 years younger and I'd kick your a**."

But Sunday afternoon in Los Angeles, Merchant said he and Floyd buried the hatchet over the weekend in Las Vegas and each apologized for what went down.

As for Justin Bieber's appearance at the Mayweather-Cotto fight ... Merchant said he was "trying to get some face time on television. I think he needs it badly."

We're not sure Merchant knows who the Biebs is.

Justin Bieber's appearance with Floyd Mayweather last night was months in the making -- and sources close to The Biebs tell TMZ ... Justin feels his new "mentor" is really just "misunderstood."

According to our sources, Mayweather asked Bieber four months ago to join him in Las Vegas for the Miguel Cotto fight ... and Bieber, a huge boxing fan, jumped at the opportunity.

We're told Floyd and Justin became friends after Floyd saw Justin's movie, "Never Say Never," and reached out to his camp. According to our sources, Floyd decided he wanted to mentor Justin and the two developed a relationship. 

Our sources say Mayweather tried to impart his work ethic on Justin, basically telling him he could develop the same level of "greatness" Floyd achieved ... if he worked as hard as Floyd did. 

We're told the two hit it off and Justin tells people he thinks Floyd is just misunderstood ... and that he is a really a "hard-working and clean-cut guy." 

Several judges would disagree, but whatever ...

Of course Floyd Mayweather took care of business last night against Miguel Cotto -- he had the dreaded masters of intimidation in his corner, like Lil Wayne, 50 Cent and ... Justin Bieber?

Bieber walked out with Mayweather before the fight and was in the ring with him after to celebrate the victory. 

It's unclear how the two hooked up, though Bieber did once compare himself to Mayweather in an interview. Earlier in the day, Bieber tweeted, "cinco de mayo.... #MayweatherCotto yeah @FloydMayweather today is a BIG day."

So we have to ask ...

Justin Bieber's super hot love interest in his new music video wants the singer's rabid female fans to know she's NOT a threat ... 'cause she's already got a man.

TMZ spoke with Rachel Barnes -- the chick who Bieber can't keep his hands off of in the new video for "Boyfriend" -- and she tells us the chemistry between the two was "only for work."



"Justin and Selena are adorably inseparable and I, myself, am already married" ... adding, "I'm a Belieber, but he's not my boyfriend." 

FYI -- Bieber's fans have a reputation for being a bit ... territorial ... and some have even sent death threats to women who got a little too close to JB ... including Kim Kardashian.

But Barnes -- who got married in La Jolla last year -- says the Biebettes have been cool so far ... adding, "It's been great to be a part of the Bieber madness ... even if only for a song."

Looking like father and son, music legend Sir Elton John and teen pop prince Justin Bieber both rocked red Sally Jessy Raphael specs this week.

Everything old is new again.

We're just sayin'.

Justin Bieber thinks he's born to be wild -- but now that Usher's convinced him to buy a super-expensive, super-fast motorcycle ... JB might be pressing his luck.

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