New Jersey DWI Lawyer: Penalties, Refusal, Interlock, and What Happens Next

What counts as DWI in New Jersey?

Under N.J.S.A. 39:4-50(a), a person commits DWI by operating a motor vehicle while under the influence of intoxicating liquor or a narcotic, hallucinogenic, or habit-producing drug, or with a blood alcohol concentration (BAC) of 0.08% or more. The statute also covers a person who permits someone who is under the influence, or at 0.08% or more, to drive a vehicle the person owns or controls.

DWI lives in Title 39, the motor vehicle code, not in Title 2C, the criminal code. That is why it is heard in the municipal court where the stop happened, and why a judge, not a jury, decides it. It is still treated seriously: the State must prove the charge, and the penalties include jail for repeat offenses.

If the case also involves a criminal charge, such as an assault by auto or another indictable offense, that part of the case can go to the county Superior Court. See indictable crimes.

What are the DWI penalties in New Jersey in 2026?

The table below summarizes the current text of N.J.S.A. 39:4-50(a) and the interlock periods in N.J.S.A. 39:4-50.17. License "forfeiture" is the statute's word for losing the right to drive.

Other costs set by the statute: a $125 surcharge (39:4-50(i)), a $100 fee to the Alcohol Education, Rehabilitation and Enforcement Fund (39:4-50(b)), and IDRC per diem fees of $75 (first-offender program) or $100 (second-offender program) (39:4-50(f)). Failing to complete IDRC requirements can bring a mandatory two-day jail term and continued suspension. The Motor Vehicle Commission also assesses insurance surcharges after a conviction.

Interlock credit instead of forfeiture (P.L.2025, c.41): for offenses on or after April 3, 2025, a person required to forfeit driving privileges under 39:4-50 may instead install an ignition interlock and receive a one-day credit against the forfeiture period for every two days it is installed. There is no credit if the DWI caused serious bodily injury to another person, or for a drug DWI. This can shorten the forfeiture periods in the table, such as 3 months at 0.15% or higher, 1 to 2 years for a second offense, and 8 years for a third. (P.L.2025, c.41)

More detail: first-offense DWI, second and third DWI, and ignition interlock rules.

Can I install an interlock before I am convicted?

Yes. Since February 19, 2024 (P.L.2023, c.191), a person arrested for DWI may, before any conviction, voluntarily install an ignition interlock in the one vehicle they own, lease, or most often drive, and ask the Motor Vehicle Commission for a license with an interlock notation. The request must include the installer's certification and documentation of the pending charge.

Doing this can matter at sentencing. Under the current statute, a person who installs early and had a valid New Jersey license in good standing at the time of the offense (and kept it in good standing until conviction) is not subject to the fine for that tier. For a 0.15%+ first offense and for second and third offenses, the person gets a one-day credit against the forfeiture period for every two days the interlock is installed with the proper license notation.

There is no credit if the DWI caused serious bodily injury to another person, or for a DWI based on drugs. Whether early installation makes sense depends on your case, so talk with a lawyer first.

Do the 2019 and 2024 DWI changes expire?

Yes, under current law. The 2019 interlock law (P.L.2019, c.248) changed most first-offense penalties from long suspensions to interlock requirements. P.L.2023, c.191 extended that law and changed several penalty periods effective February 19, 2024, and the NJ Courts Directive #04-24 explains that these provisions expire on January 1, 2029. A 2025 law (P.L.2025, c.41), which lets a driver install an interlock instead of forfeiting and earn one day of credit for every two days installed (for offenses on or after April 3, 2025), has the same expiration date. If the Legislature does not act before then, the penalty structure could change again, so check the date at the top of this page.

What happens if I refuse the breath test?

By driving on New Jersey roads, you are deemed to consent to breath testing after a lawful DWI arrest (N.J.S.A. 39:4-50.2). Refusing is a separate violation under N.J.S.A. 39:4-50.4a. The municipal court decides it by a preponderance of the evidence, asking whether the officer had probable cause to believe you were driving under the influence, whether you were arrested, and whether you refused.

For a first offense, a refusal revocation can run at the same time as, or after, a DWI revocation from the same incident. For a second or later offense, it must run after the DWI revocation. Read more on the refusal page.

DWI vs. refusal: how are they different?

Can Alcotest 9510 results still be challenged?

Yes, case by case. New Jersey began replacing the Alcotest 7110 with the Alcotest 9510. On May 1, 2023, the Supreme Court stayed DWI cases based only on 9510 results while it considered the device's reliability in State v. Cunningham. On December 19, 2025, the Court dismissed that case and lifted the stay, so prosecutions using the 9510 can go forward. The Court did not rule on whether the 9510 is scientifically reliable, and its order says defendants in individual cases may still challenge the device's reliability. See the NJ Courts notice and order and our Alcotest 9510 page.

What happens after a DWI arrest in New Jersey?

1. At the station. You are asked for breath samples. You usually leave with tickets (summonses) for DWI and often for refusal or other violations. Keep every paper.
2. Before the first court date. Write down what you remember: where you were, what you drank or took, the timing, the tests you were asked to do. Do not post about it.
3. First appearance in municipal court. The court confirms your charges and your right to a lawyer.
4. Discovery. Your lawyer requests police reports, body-worn and dash camera video, Alcotest data, and calibration and maintenance records.
5. Motions and negotiation. Issues with the stop, the arrest, or the breath test can be raised by motion. Under the current statute, a plea agreement is authorized on the prosecutor's recommendation with an appropriate factual basis.
6. Trial or plea, then sentencing. If convicted, the judge imposes the statutory penalties and you are referred to the IDRC.
7. Appeal. A municipal conviction can be appealed to the Superior Court. The deadline is short, generally 20 days.

How are DWI cases defended?

• The reason for the stop and whether the officer had grounds to arrest
• How field sobriety tests were explained, performed, and recorded
• The Alcotest procedure: the observation period, operator credentials, and the device's records
• Whether the refusal warning was read and understood, including language barriers
• Blood test collection and lab handling in drug or blood cases
• Whether a prior conviction counts, including the 10-year step-down and out-of-state priors

We do not promise outcomes. We review the evidence, explain your options, and let you decide.

Do prior DWIs from years ago or from another state count?

If a second offense happens more than 10 years after the first, the court treats it as a first offense for sentencing. If a third offense happens more than 10 years after the second, it is sentenced as a second offense. A conviction in another state for a substantially similar law counts as a prior unless the defendant shows by clear and convincing evidence it was based only on a BAC under 0.08%.

What else does a DWI conviction affect?

• Driving and insurance. The conviction goes on your driving record, and the Motor Vehicle Commission assesses insurance surcharges. Your insurance premiums can rise.
• Interlock costs. You pay for installing and maintaining the interlock device.
• Work. Jobs that require driving or a commercial license are affected; commercial license holders face separate federal and state rules.
• Record. Because DWI is a motor vehicle offense, it stays on your driving abstract; New Jersey's expungement law (N.J.S.A. 2C:52) covers criminal and disorderly persons records, not motor vehicle violations.
• Future cases. A conviction counts as a prior offense if there is another DWI within 10 years.

Where will my DWI case be heard?

In the municipal court of the town where the stop happened. If you were stopped in Newark, that is the Newark Municipal Court; in Jersey City, the Jersey City Municipal Court; and so on. Your summons names the court. We handle cases from our Newark office across our service counties: see where we handle cases.

Recent changes to New Jersey law on this topic

• 2019-12: P.L.2019, c.248: interlock replaces most first-offense suspensions.
• 2024-02-19: P.L.2023, c.191 takes effect: voluntary pre-conviction interlock, revised forfeiture and interlock periods; expiration extended to Jan. 1, 2029.
• 2025-04-03: P.L.2025, c.41 signed: for offenses on or after this date, a driver may install an interlock instead of forfeiting and earn a one-day credit for every two days installed (no credit for drug DWIs or serious bodily injury). Expires Jan. 1, 2029.
• 2025-12-19: NJ Supreme Court dismisses State v. Cunningham and lifts the Alcotest 9510 stay without a reliability ruling.