Assault Weapons Lawyers in Bay Area (PC 30600)

A single firearm modification, one part that crosses a technical line you didn’t know existed, and suddenly you’re facing years in state prison. California’s assault weapons laws are among the most complex in the country, and the difference between a legal rifle and a felony charge can come down to millimeters.

Most people charged under Penal Code section 30600 are not career criminals. They are gun owners, collectors, and hobbyists who believed their firearm was configured legally. The technical definitions that separate a lawful rifle from a prohibited “assault weapon” are so intricate that even licensed dealers get them wrong. That complexity is exactly where a strong defense begins.

The Nieves Law Firm Criminal Defense Attorneys has the resources and courtroom experience to challenge these charges aggressively. Our team understands the technical firearms classifications that drive these prosecutions, and we know how to dismantle the prosecution’s case at the element level. If you are facing assault weapons charges anywhere in the Bay Area, our weapons crimes defense attorneys are ready to fight for you — contact our team today for a consultation.

How California Defines Assault Weapons

California does not use the colloquial understanding of “assault weapon.” The legal definition is narrow, technical, and spread across multiple code sections, which creates both prosecution challenges and defense opportunities.

There are two primary ways a firearm qualifies as an assault weapon under California law. The first is the Roberti-Roos list under Penal Code section 30510, which names specific makes and models of firearms that are categorically prohibited.¹ The second, and far more commonly litigated, is the generic characteristics test under Penal Code section 30515, which defines assault weapons based on a combination of features such as a pistol grip, thumbhole stock, flash suppressor, or detachable magazine on a semiautomatic centerfire rifle.²

A .50 BMG rifle is separately defined under Penal Code section 30520 and subject to the same prohibitions.³

This matters for your defense because the prosecution must prove your specific firearm meets one of these definitions. If your rifle was built with a fixed magazine, a featureless configuration, or other compliance modifications, it may fall outside the statutory definition entirely.

What the Prosecution Must Prove

To secure a conviction under Penal Code section 30600, the prosecution carries the burden of proving every element beyond a reasonable doubt. Under the applicable jury instructions, these elements include⁴:

You engaged in a prohibited act with the weapon

The statute covers a wide range of conduct: manufacturing, distributing, transporting, importing into California, keeping for sale, offering or exposing for sale, giving, or lending an assault weapon or .50 BMG rifle.⁵ Each of these acts is treated as a separate violation. The prosecution must prove you committed at least one of them. Merely being near the weapon or knowing someone who possesses one is not enough.

The weapon qualifies as an assault weapon or .50 BMG rifle under California law

This is frequently the most contested element. The prosecution must establish, through expert testimony or other evidence, that the specific firearm meets the technical legal definition. For weapons classified under the generic characteristics test, this requires a detailed examination of the firearm’s features. A single modification, such as removing a flash suppressor or pinning a magazine, can take the weapon outside the statutory definition.

You knew or reasonably should have known the weapon had prohibited characteristics

California law requires a knowledge element. The prosecution must show you were aware, or should have been aware, that the firearm had the features that made it an assault weapon. This is a critical defense point. If you purchased the firearm believing it was California-compliant, or if it was modified by a third party without your knowledge, the prosecution may not be able to establish this element.

You did not have a valid permit or exemption

Several statutory exemptions exist under Penal Code sections 30610 through 30665, covering law enforcement, military personnel, licensed dealers, and individuals who lawfully registered their weapons during prior registration windows.⁶ The burden typically shifts to the defense to raise the exemption, but the prosecution must then disprove it beyond a reasonable doubt.

Penalties for Assault Weapons Charges

Penal Code Section 30600 Penalties

A violation of PC 30600 (manufacturing, distributing, transporting, importing, selling, giving, or lending an assault weapon) is a straight felony.⁷

Penal Code Section 30605 Penalties

Possession of an assault weapon under PC 30605 is treated differently from the trafficking and manufacturing conduct covered by PC 30600.⁸ Depending on the circumstances, possession may be charged as either a felony or a misdemeanor.

The distinction between PC 30600 and PC 30605 is significant. If you are charged under 30600 for transporting a weapon that you possessed, your attorney may be able to negotiate a reduction to a possession charge under 30605, which carries substantially less prison exposure and may be eligible for probation.

The Technical Definition Problem in Assault Weapons Cases

What makes California assault weapons prosecutions unique is that the entire case often hinges on a technical classification question rather than criminal intent. This creates a distinct defense landscape that doesn’t exist in most other weapons cases.

Under the generic characteristics test in Penal Code section 30515, a semiautomatic centerfire rifle becomes an “assault weapon” only when it has certain feature combinations.⁹ A rifle with a detachable magazine and a pistol grip is prohibited. The same rifle with a fixed magazine or without the pistol grip is legal. The line between felony and lawful ownership can literally depend on whether a magazine release requires a tool to operate.

This technical complexity has real consequences for prosecution. The California Department of Justice maintains a list of specifically named assault weapons, but the generic characteristics definition requires a feature-by-feature analysis of the actual firearm. Prosecutors must present expert testimony from a firearms examiner who can testify that the weapon, as configured at the time of seizure, met the statutory definition.

From a defense perspective, this creates multiple angles of attack. Was the magazine truly “detachable” under the legal definition? Was the feature identified by the examiner actually a “flash suppressor” or a muzzle brake (which is not a prohibited feature)? Did the examiner test the firearm’s configuration, or simply rely on a visual inspection? These technical questions can make or break a case, and they require defense counsel who understands firearms mechanics as well as the law.

Defense Strategies That Apply to Your Case

Challenging the Weapon Classification

If the firearm does not actually meet the legal definition of an assault weapon, there is no crime. This defense requires a detailed, independent examination of the weapon by a qualified firearms expert. Many firearms are built or modified to comply with California law using features like fixed magazines, featureless grips, or magazine locks. If the prosecution’s examiner misidentified a feature or failed to properly test the weapon’s configuration, the classification may be wrong.

Consider this scenario: you purchased a rifle from a California dealer that was sold as compliant. The dealer installed a magazine lock device. During a traffic stop, police seized the rifle and their examiner concluded the magazine lock was not functioning properly, making the magazine “detachable.” A defense expert who examines the device and finds it was functional at the time of sale can undermine the prosecution’s entire case.

Lack of Knowledge Defense

You cannot be convicted if you did not know, and had no reason to know, that the firearm had assault weapon characteristics. This defense is particularly strong in situations involving inherited firearms, weapons modified by a previous owner, or firearms purchased from out-of-state dealers who represented them as California-legal. The prosecution must prove your mental state, and reasonable ignorance of technical firearms classifications is a legitimate defense.

Fourth Amendment Suppression

How law enforcement discovered the weapon matters enormously. If the firearm was found during an unlawful traffic stop, a warrantless home search, or a search that exceeded the scope of a valid warrant, the evidence may be suppressed entirely. Without the weapon itself, the prosecution has no case.

In the Bay Area, firearms are frequently discovered during vehicle stops or during searches connected to unrelated investigations. Our team scrutinizes every aspect of the search, from the initial justification for the stop to the specific actions officers took once the weapon was located.

Constructive Possession Challenge

When a weapon is found in a shared space such as a home with multiple residents, a vehicle with multiple occupants, or a storage unit, the prosecution must prove you specifically had knowledge of and dominion and control over the weapon. Mere proximity is not enough. If the weapon belonged to a roommate, family member, or was stored in a common area, the prosecution may not be able to establish that you possessed it.

Lawful Registration or Exemption

California has offered several registration windows over the years, allowing owners of assault weapons to register them lawfully under Penal Code section 30900.¹⁰ If your weapon was registered during one of these periods, possession is not a crime (though other conduct like lending or selling may still be prohibited). Similarly, statutory exemptions exist for law enforcement, military, licensed dealers, and certain other categories.¹¹

Temporary or Transitory Possession

If you came into possession of the weapon briefly and for a lawful purpose, such as to turn it over to law enforcement, remove it from a dangerous situation, or transport it for disposal, California courts have recognized this as a valid defense in limited circumstances.

The Second Amendment and California’s Assault Weapons Ban

The constitutional landscape surrounding California’s assault weapons laws is actively evolving, and this creates both opportunities and uncertainty for defendants.

In 2022, the U.S. Supreme Court’s decision in New York State Rifle & Pistol Association, Inc. v. Bruen established a new framework for evaluating firearms regulations under the Second Amendment.¹² Under Bruen, the government must demonstrate that a firearms regulation is “consistent with this Nation’s historical tradition of firearm regulation.” This standard has prompted renewed challenges to California’s assault weapons ban.

In Miller v. Bonta, a federal district court in the Southern District of California struck down California’s assault weapons ban as unconstitutional.¹³ That decision was vacated and is currently on appeal. The outcome of this and related litigation could fundamentally change the legal landscape for assault weapons charges in California.

While a constitutional challenge is not a guaranteed defense in any individual case, it is an important consideration in case strategy. Depending on the timing and posture of your case, preserving constitutional arguments for appeal may be a critical part of your defense plan. Our team monitors this litigation closely and incorporates constitutional arguments where they can benefit our clients.

Collateral Consequences Beyond Prison

A conviction under PC 30600 or PC 30605 carries consequences that extend well beyond the sentence imposed by the court.

Lifetime Firearms Ban

Any felony conviction in California results in a lifetime prohibition on possessing firearms under both state and federal law.¹⁴ Even a misdemeanor conviction under PC 30605 triggers a ten-year firearms prohibition under California law. For gun owners and collectors, this consequence can be more significant than the prison sentence itself.

Immigration Consequences

Firearms offenses are generally considered deportable offenses under federal immigration law. Non-citizens convicted of assault weapons charges face potential removal proceedings, denial of naturalization, and bars to reentry. If you are not a U.S. citizen, immigration consequences must be a central consideration in your defense strategy, and any plea agreement should be carefully evaluated for immigration impact.

Employment and Professional Licensing

A felony conviction can disqualify you from employment in law enforcement, military service, security, education, healthcare, and many licensed professions. California’s professional licensing boards have broad discretion to deny or revoke licenses based on criminal convictions, and a weapons felony is treated with particular seriousness.

Post-Conviction Relief

For those convicted of the wobbler offense under PC 30605, there may be options for relief after completing your sentence. Felony reduction to a misdemeanor under Penal Code section 17(b), expungement under Penal Code section 1203.4, or a certificate of rehabilitation may be available depending on your circumstances.¹⁵ These options are generally not available for the straight felony under PC 30600 unless the conviction is reversed on appeal.

Offenses Commonly Charged Alongside Assault Weapons Violations

Assault weapons charges rarely appear in isolation. The prosecution frequently adds related charges that increase both complexity and sentencing exposure.

Each additional charge carries its own elements that the prosecution must independently prove. A strong defense often involves challenging the weakest charges first, which can create leverage to resolve the remaining counts favorably.

Quick Reference

Why The Nieves Law Firm Criminal Defense Attorneys Fights Assault Weapons Cases Differently

Assault weapons cases are fundamentally different from other criminal charges because they turn on technical classifications, not violent conduct. The prosecution’s case depends on proving that a specific firearm, as configured at a specific moment, met a complex statutory definition. That requires a level of technical scrutiny that many defense attorneys are not prepared to deliver.

Our team at The Nieves Law Firm Criminal Defense Attorneys brings the resources of one of the largest criminal defense teams in the Bay Area to every weapons case we handle. We work with independent firearms experts, challenge the prosecution’s technical evidence at every stage, and fight to protect your rights, your freedom, and your future.

Cases involving assault weapons charges in Alameda County are typically heard at the Rene C. Davidson Courthouse in Oakland, with cases from the southern part of the county proceeding through the Fremont Hall of Justice.

If you are facing charges under PC 30600 or PC 30605, the earlier you get defense counsel involved, the stronger your position becomes. Evidence can be preserved, witnesses can be identified, and constitutional challenges can be raised before critical deadlines pass. Schedule a consultation with our team and take the first step toward protecting what matters most.