Wisconsin Act 100: New Law Increases Penalties for Carfentanil Offenses

Analysis of 2025 Wisconsin Act 100 (Senate Bill 692)

Wisconsin has significantly intensified its legal stance on synthetic opioids with the enactment of 2025 Wisconsin Act 100. Signed into law in March 2026, this legislation specifically targets carfentanil – a substance significantly more potent than fentanyl – by creating a new, graduated penalty structure for its manufacture, distribution, and possession with intent to deliver.

Prior to this Act, carfentanil offenses were generally prosecuted under broader narcotic statutes. By carving out carfentanil into its own statutory category, the legislature has signaled a move toward much harsher penalties based on the weight of the substance involved.

For those facing drug-related allegations, Act 100 represents a substantial shift in potential prison exposure. If you or a loved one are facing charges involving synthetic opioids, contacting a Wisconsin drug defense attorney is critical to navigating these new, severe sentencing guidelines.

New Graduated Penalties for Carfentanil

The centerpiece of Act 100 is the creation of specific felony classifications based on the amount of carfentanil involved in a case. Under the new Wis. Stat. § 961.41 (1)(dn) and (1m)(dn), the penalties are as follows:

These penalties apply both to the actual delivery of the drug and to possession with the intent to deliver. By establishing these tiers, the law ensures that even relatively small amounts of the substance can lead to decades of imprisonment.

Determining the Weight: The “Mixture” Rule

One of the most critical aspects of Act 100 is how the state calculates the weight of the drug. The law clarifies that when determining the amount for charging purposes, the weight includes:

• The carfentanil itself.
• Any controlled substance analog.
• Any compound, mixture, or diluent mixed with it (such as cutting agents).

In practice, this means that if a very small amount of carfentanil is mixed into a large amount of another substance (like baking soda or another drug), the entire weight of the mixture is used to determine the felony level. This “mixture rule” can easily push a defendant into the 50+ gram category, triggering a Class C felony charge even if the pure carfentanil content is minimal.

Five-Year Penalty Enhancer

Act 100 also adds carfentanil to the list of substances subject to penalty enhancers under Wis. Stat. § 961.49.

If a person distributes or possesses carfentanil with intent to distribute near certain protected places, the maximum term of imprisonment may be increased by an additional 5 years. These locations typically include:

• Schools and school buses.
• Public parks and swimming pools.
• Youth centers and community centers.
• Certain housing projects.

Prosecution of Multiple Violations

The Act also amends Wisconsin’s criminal procedure statutes (Wis. Stat. § 971.365) to allow prosecutors to combine multiple carfentanil violations into a single transaction. If several incidents of distribution were part of a “single intent and design,” they can be prosecuted as one crime, which often results in a higher total weight and, consequently, a higher felony classification.

Key Takeaways from Wisconsin Act 100

• Specific Carfentanil Charges: Carfentanil now has its own graduated penalty scale, separate from other narcotic drugs.
• Higher Felony Classes: Depending on the weight, offenses can range from a Class E to a Class C felony (up to 40 years in prison).
• Entire Weight Counts: The presence of any amount of carfentanil in a mixture allows the state to charge based on the total weight of the entire mixture.
• Zone Enhancers: Distributing carfentanil near schools or parks now triggers a 5-year penalty increase.
• Analogs Included: The law applies equally to controlled substance analogs that are chemically similar to carfentanil.

What This Law Means Going Forward

Act 100 reflects the ongoing legislative effort to curb the opioid crisis through increased deterrence and longer sentences. For the legal community, this law will likely lead to more complex litigation regarding the chemical composition of seized substances and the methods used by crime labs to weigh “mixtures.” Because carfentanil is so potent, the margin of error for a defendant between a Class E and a Class C felony is incredibly slim.