WASHINGTON, DC - JANUARY 10: Hunter Biden (C), son of U.S. President Joe Biden, and his lawyer Abbe Lowell (R) depart a House Oversight Committee meeting at Capitol Hill on January 10, 2024 in Washington, DC. The committee is meeting today as it considers citing him for Contempt of Congress. (Photo by Kent Nishimura/Getty Images)
CNN  — 

Special counsel David Weiss forcefully pushed back Tuesday against Hunter Biden’s allegations that he was only indicted on gun charges because of right-wing bias.

Also, for the first time, Weiss publicly released a photo of the Colt Cobra .38 revolver that Biden is accused of illegally buying and possessing in 2018. (He has pleaded not guilty.) An image of the gun was included in a 52-page court filing.

President Joe Biden’s son is seeking to have the three gun-related felony charges thrown out, on the theory that they were only filed because Weiss caved to Republican pressure to indict him as the 2024 campaign got underway. Weiss rejected those arguments on Wednesday.

Weiss’ team blasted the claims as a “conspiracy theory.”

“Stripped of its bluster, the defendant’s theory of vindictiveness is simply not credible,” special counsel prosecutors wrote in the filing. “Left with the inconvenient truth of trying to explain how this could happen during the Biden Administration, the defendant suggests that evil motives are lurking deep within the Department of Justice.”

They added: “This theory is a fiction designed for a Hollywood script.”

Twenty-five cartridges of Hornady “American Gunner” ammunition and a Colt Cobra 38SPL revolver that Hunter Biden purchased from a gun store in Wilmington, Delaware, in October 2018.

Hunter Biden’s lawyers contend that Weiss only abandoned a prior deal – that would’ve resolved the gun probe without an indictment – because of public pressure from former President Donald Trump, congressional Republicans, and conservatives within the Justice Department.

The gun indictment accuses Biden of illegally buying the weapon, because he allegedly lied on an ATF form when he said he wasn’t addicted to drugs at the time. It’s also against the law to possess a gun while using illegal drugs – and Biden possessed the gun for about two weeks in 2018, before it was discarded.

In addition to the gun charges, Biden is also facing a separate tax indictment. He pleaded not guilty to those charges last week.

Special counsel says evidence in gun case is ‘overwhelming’

Federal prosecutors revealed new details about Biden’s struggles with drug addiction in the court filing as they pushed back on allegations that the prosecution is politically motivated.

They presented these details to support their argument that the charges were brought because the evidence is “overwhelming” – and not because of any political bias.

Investigators said they obtained a search warrant for backups of Biden’s electronic devices as part of the tax probe – and then found messages implicating him in drug use while possessing the gun. They also said they found a photo of crack cocaine from his phone that was taken on the day he purchased the gun in Delaware, on October 12, 2018.

CNN has reached out to Hunter Biden’s lawyers for comment.

Biden has spoken openly about his addiction to alcohol and crack cocaine, including in his memoir, which prosecutors ultimately ended up using to build the gun case against him. He has accused his GOP critics of weaponizing his personal struggles for political gain. He testified at a court hearing last year that he’s been sober since 2019.

Investigators said they found texts between Biden and his girlfriend at the time – his brother’s widow, Hallie Biden – where he said he “was sleeping on a car smoking crack” and that he was “waiting for a dealer named Mookie.”

The couple also fought over the fact that she threw out his gun, after finding it in his car, 11 days after he bought it, according to the filings.

“You say I invade your privacy. What more can I do than come back to you to try again. And you do this???? Who in their right mind would trust you would help me get sober,” Hunter Biden wrote, according to the filings.

According to the filings, Hallie Biden replied, “I’m sorry, I just want you safe. That was not safe. And it was open unlocked and windows down and the kids search your car. You have lost your mind hunter. I’m sorry I handled it poorly today but you are in huge denial about yourself and about that reality that I just want you safe.”

Weiss’ team also revealed in the filing that when investigators examined Hunter Biden’s leather gun pouch last year, they found “a white powdery substance” on the item, which had been seized years earlier and was being held in a state police vault. An FBI chemist later confirmed that it was cocaine, the filing said.

“Investigators literally found drugs on the pouch where the defendant had kept his gun,” prosecutors wrote.

New details on controversial laptop

The filing appears to contain Weiss’ first public confirmation that his team examined a controversial laptop connected to Biden, which is at the center of a years-long saga involving embarrassing email disclosures and leaked nude photos.

Weiss said his team examined “the defendant’s Apple MacBook Pro, which he had left at a computer store.” This appears to be the first time the Justice Department has publicly said it belonged to Hunter Biden.

Biden has sued the repair shop owner and the Trump allies he worked with to disseminate the laptop’s explosive materials to right-wing media outlets. He hasn’t ever taken ownership of the laptop and has suggested the leaked materials could’ve been “hacked” or were Russian fabrications.

The lawsuits acknowledged that some of the leaked “data” was authentic, but danced around the question of whether the laptop itself belonged to, or was dropped off by, Biden.

Federal prosecutors said the information they gleaned from the laptop was “largely duplicative” of material they already obtained from an earlier search warrant. That warrant, obtained in August 2019, was for Biden’s iCloud account, which contained backups of his electronic devices, including the laptop.

According to Weiss’ filing in court Tuesday, prosecutors also have handed over the copy of the laptop that they had obtained to Biden’s defense team, as part of the required evidence productions before trial. The filing indicated the laptop is likely to come into play when the case is presented before a jury.

This story story has been updated with additional details.

CNN’s Paula Reid contributed to this report.