First DWI in New Jersey: penalties, interlock and what happens next

DWI is a traffic offense, but a serious one

New Jersey treats driving while intoxicated under N.J.S.A. 39:4-50 as a motor vehicle offense rather than a crime. The New Jersey Supreme Court has long described it that way, and it is why DWI cases are heard in municipal court by a judge, without a jury.

That label can be misleading. A DWI conviction still brings fines, mandatory programs, insurance surcharges, possible jail and limits on your driving, and it counts as a prior offense if you are ever charged again.

First offense penalties by blood alcohol level

The 2019 amendments to N.J.S.A. 39:4-50 (P.L.2019, c.248) reshaped first offense penalties around ignition interlock devices. Rather than a long suspension, most first offenders forfeit their license only until they install an interlock in the car they drive.

• BAC 0.08% to under 0.10%: $250 to $400 fine, up to 30 days in jail at the judge's discretion, IDRC, and an interlock required for 3 months
• BAC 0.10% to under 0.15%: $300 to $500 fine, up to 30 days in jail, IDRC, and an interlock for 7 months to 1 year
• BAC 0.15% or higher: $300 to $500 fine, up to 30 days in jail, IDRC, a 4 to 6 month license forfeiture with an interlock, then an interlock for 9 to 15 months after your license is restored
• Drug-impaired driving: $300 to $500 fine and a 7 month to 1 year license forfeiture

Fees, the IDRC and the surcharge

On top of the fine, the MVC lists additional fees for a first DWI, including a $230 IDRC fee and payments to the Drunk Driving Enforcement Fund, the Alcohol Education and Rehabilitation Fund, and the Neighborhood Services Fund.

Every first offender must attend the Intoxicated Driver Resource Center for 12 to 48 hours, served over two consecutive days, at least six hours each day. The IDRC evaluates you and may require further treatment.

The MVC also imposes an insurance surcharge of $1,000 a year for three years. That is separate from any increase in your car insurance premium, which can be significant.

Refusing a breath test

New Jersey's implied consent law means drivers agree to provide breath samples after a lawful DWI arrest. Refusing is a separate offense under N.J.S.A. 39:4-50.4a.

For a first refusal, the penalties include a $300 to $500 fine, forfeiture of your license until an interlock is installed, and referral to the IDRC. State traffic safety materials also list the $1,000 yearly surcharge for three years. A refusal can be charged together with a DWI, so some people face both.

Recent changes: plea deals and interlock credit

For decades, New Jersey municipal courts did not allow plea agreements in DWI cases. That changed in 2024. A law effective February 19, 2024 (P.L.2023, c.191) authorizes plea agreements in DWI cases on the prosecutor's recommendation, and the New Jersey Supreme Court withdrew its old ban on DWI plea bargaining on February 23, 2024. Whether a plea is offered depends on the facts and the prosecutor.

A 2025 law (P.L.2025, c.41) lets people facing a license forfeiture under the DWI statute install an interlock instead and earn one day of credit against the forfeiture for every two days the device is installed. It does not apply when the DWI caused serious bodily injury or involved drug impairment.

What happens in court

After an arrest, you will receive summonses with a municipal court date. Your lawyer can request discovery, including police reports, body camera and dashcam video, and records about the breath test instrument and the officer's training. Defenses can involve the reason for the stop, how field sobriety tests were given, and whether breath testing followed required procedures.

You can hire a private lawyer, and you can ask the municipal court whether you qualify for a public defender.