In their rulings, courts have already taken judicial notice that:

Children exposed to involuntary smoking, or passive smoking, are more likely to develop:

For those children who have asthma, exposure to secondhand smoke increases the frequency and strength of asthma attacks, the chance of accidental cigarette burns and hazards from fires and, as adults, the development of lung cancer, heart disease and cataracts. The children of smokers are also more likely to become smokers.

In New Jersey, as in most jurisdictions, the law on the issue of parental smoking and custody is far from settled. Currently, only one reported New Jersey case considered the effects of secondhand smoke on children in a custody context. In Unger v. Unger, 274 N.J. Super. 532 (Ch. Div. 1994), the court was presented with a motion to modify a consent order as to custody of two children. By virtue of a prior consent arrangement, the parties had placed several restrictions on parental smoking. First, they agreed that neither party would smoke in the presence of the children in the home and automobiles. Next, the mother, the custodial parent, would be restricted to only smoking in her bedroom when the children were present in the home. The mother was permitted to smoke in the living quarters of the house only when the children were not present, and provided further that she purchase an air purifier.

Notwithstanding the restrictions on smoking, the father in Unger argued that harm was inflicted upon one of the children due to secondhand smoke. Although not arguing non-compliance with the smoking restrictions, the father alleged that one child suffered from "a deep chesty cough . . . and that it decreases when he resides . . . in a smoke free environment." The father made application to reopen the custody issue maintaining that only he could provide the children with a totally smoke free environment and spare them from further harm. In New Jersey, courts are free to make any custody arrangement that serves the best interests of the child, and the courts consider several factors including "the safety of the child" and the "fitness of the parents."

After considering medical testimony and the children's medical records, the court found that the restrictions in the consent order left the child vulnerable to harm from the mother's cigarette smoke. The court stated that under the best interests of the child standard, the effects of smoking on children should be considered "as a health and safety factor."

Unger is clearly not the last word on smoking and child custody. Indeed, Unger reserved for a final hearing the issue of custody and therefore it is unclear as to the weight that the trial court ultimately afforded the issue as against other custody factors. As the trial court in Unger did not reach many of the complexities of the smoking issue, it is necessary to examine the developing case law from other jurisdictions to understand some of the important issues in smoking cases and where the trend in the law is headed.