Diaz, 31, is scheduled to appear in San Joaquin County Court in California on Thursday to face eight total charges stemming from two alleged driving while under the influence incidents.
Fertitta told ESPN.com that he has not spoken to Diaz since news broke of the charges two weeks ago but said he doesn't think they will prevent the fight, which headlines UFC 183 in Las Vegas.
"That's for him and his people," Fertitta said. "We don't really get involved on that level other than staying in touch to understand what's happening.
"We're going to find out more when he has his court date. I don't necessarily think, and this is me personally, the charges would prevent the fight from happening. I've never seen a situation where a commission didn't license someone to fight because of a DUI."
In terms of the UFC sanctioning a punishment, Fertitta said the promotion would address the issue after Diaz's case goes through the legal system.
"Look, clearly it's a potential violation of our code of conduct," Fertitta said. "It's something we have to sit down and take a look at, but I can't make any decisions or rush to judgment until this thing kind of plays out. That's why the legal system is there. If we start handing down decisions before we know the facts, it's not a good situation."
On Nov. 28, Diaz was arrested and charged with DUI, DUI with an alcohol or drug level above .08 and unsafe speed for prevailing conditions, according to San Joaquin County Court spokeswoman Stephanie Bohrer. An additional charge of failing to appear after written promise was added in December, when Diaz skipped a mandatory court appearance.
On Sept. 6, Diaz was arrested again in Stockton, California, and charged with DUI, DUI with an alcohol or drug level above .08, driving with a suspended license and resisting arrest. The resisting arrest charge stems from Diaz attempting to induce himself to vomit at the Lodi Police Department in an effort to remove alcohol from his body.
Diaz (26-9) hasn't fought since he lost a unanimous decision to Georges St-Pierre in a UFC title fight in March 2013. Diaz renegotiated his UFC contract earlier this year and agreed to fight former middleweight champion Silva (33-6), who will return after missing all of 2014 due to a serious leg injury.