N.J. Stat. § 54:40B-10
If a return required by this act is not filed, or if a return when filed is incorrect or insufficient, the amount of tax due shall be determined by the director from such information as may be available. If necessary, the tax may be estimated on the basis of external indices, such as purchases, location, scale of charges, comparable charges, number of employees or other factors. Notice of the determination shall be given to the distributor, wholesaler, retail dealer or consumer liable for the payment of the tax. The determination shall finally and irrevocably fix the tax unless the wholesaler, distributor, retail dealer or consumer against whom it is assessed, within 30 days after the notice date of the determination, shall apply to the director for a hearing, or unless the director on the director's motion shall redetermine the same. After the hearing the director shall give notice of the determination to the wholesaler, distributor, retail dealer or consumer against whom the tax is assessed.
N.J.S. § 54:40B-10