Does a parent have to justify cutting off a grandparent's contact, or is it presumed to be their right?

A parent doesn't need a court's permission in advance to limit or end a grandparent's contact, and a fit parent's own judgment about who spends time with their child is given real, meaningful respect by the courts - it isn't treated as something that needs pre-approval. But if a grandparent brings a contact application challenging that decision, the parent will typically need to explain their reasoning as part of the evidence before the court, since the judge is deciding what actually serves the child's best interests, not simply confirming that a parent is allowed to make the decision.

In practice, this means a parent doesn't have to justify the decision unless and until it's actually challenged in court, at which point the strength of the parent's reasons becomes very relevant to the outcome. A parent with genuine, well-founded concerns is in a strong position; a parent whose reasons don't hold up to scrutiny, or who can't point to anything beyond a general preference, is more vulnerable to a court ordering contact despite the parent's wishes. Either side in this kind of dispute benefits from focusing on concrete, child-centred evidence rather than the underlying adult relationship.