A ruling by the state’s highest court yesterday will give a boost to grandparents seeking court orders allowing them to visit their grandchildren over parental objections.

State courts across the country have been grappling with grandparent visitation cases since the U.S. Supreme Court issued six opinions in a single grandparent visitation case in 2000. Taken together, the opinions offer states little guidance on the issue.

Yesterday’s unanimous ruling, by the New York Court of Appeals, places New York among the states that require grandparents to overcome a relatively low standard before a judge can override a parent’s wishes and grant grandparents access to a child.

The ruling is the first by the Court of Appeals to uphold the constitutionality of New York’s grandparent visitation statute since the fractious Supreme Court case, Troxel v. Granville. Under New York law, a grandparent is allowed to ask a judge for court-ordered visitation rights if at least one of the child’s parents is dead or under circumstances when “equity would see fit to intervene.”

Critics of grandparent visitation laws say they encourage courts to intrude into family matters.

In the current case, a Suffolk County father said New York’s grandparent visitation law violated his 14th Amendment right to raise his family as he saw fit. The man, identified in court papers by his initials, P.D., had cut off all contact between his 13-year-old son and the 82-year-old mother of his deceased wife. The grandmother, Ethel Schutz, went to court to get a visitation order.

But the Court of Appeals, in a 12-page decision by Judge Susan Read, held that New York’s law was constitutional because it gave proper deference to the wishes of parents.

There was “no abuse of discretion,” Judge Read wrote, when a lower court ordered that Ms. Schutz be allowed to take her grandson for weekly dinners, a weekend every month, and an extended summer visit.

The court said the trial judge, Sandra Lynne Sgroi of Suffolk County, had enumerated good reasons for overriding the father’s authority and granting the visitation.

In deciding that contact with the grandmother was “in the child’s best interest,” Judge Read wrote that Judge Sgroi had considered factors including the grandmother’s ability to be a caregiver, the child’s wishes, and the “reasonableness” of the father’s objections.

This calculus, the court ruled, “employed the strong presumption that the parent’s wishes represent the child’s best interests, as our statute requires.”

“While this presumption creates a high hurdle, the grandmother in this case surmounted it,” the decision reads, noting that the grandmother had played the role of a “surrogate, live-in mother” for the child for four years.

Ms. Schutz, who lives in East Hampton, moved to the family’s home in Huntington when her daughter became terminally ill and stayed after her death.

By 2002, the father, a professor at Touro Law Center, had a falling-out with Ms. Schutz. Disputes ranged from disagreements over the boy’s bedtime to his tooth-brushing habits. The father said he felt Ms. Schutz was undermining his authority with the child, according to court documents. He cut off all contact between his son and Ms. Schutz.

“The presumption that a fit parent’s decisions are in the child’s best interests is a strong one,” Judge Read wrote. Nonetheless, Judge Read suggested that parents should have to put forward stronger reasons than “parent-grandparent antagonism” when arguing in court against grandparent visitation rights.

“An acrimonious relationship is generally not sufficient cause to deny visitation,” Judge Read, who was nominated to the bench by Governor Pataki, wrote.

An Indiana attorney who follows grandparent visitation cases nationwide, Karen Wyle, called yesterday’s decision a “fairly mainstream approach” to the issue.

A Philadelphia attorney who has asked the Supreme Court to review a recent grandparent visitation decision in Pennsylvania, Howard Bashman, said it will be interesting to see how New York courts apply yesterday’s decision in cases where the grandparent has not lived with the child or played such a care-giving role.

Yesterday’s decision, Mr. Bashman said, “does allow the trial judge to quite easily substitute his or her own view of what is best for the child for the parent’s view.”

The father declined to comment, responding via e-mail that any publicity the case may garner is not in his son’s interest.