Lizzio v. Jackson
Supreme Court of New York
226 A.D.2d 760 (1996)
Lizzio (plaintiff) and Jackson (defendant) divorced in 1991 with a joint custody agreement giving Jackson primary physical custody and Lizzio liberal visitation, incorporated into the divorce judgment. Three years later, Lizzio petitioned to modify custody because Jackson smoked around the children, one of whom had suffered from asthma since 1986 - though Jackson's smoking wasn't new, having predated the 1991 divorce. The family court nonetheless modified custody, awarding Lizzio primary physical custody based on the secondhand-smoke health risk, and Jackson appealed.
Whether a potential threat to a child's health, standing alone, qualifies as changed circumstances warranting modification of an existing custody arrangement.