In some situations, spouses or former spouses may need to refute the presumption of paternity that arises when a child is born during or within 300 days after the parties’ marriage. In other situations, unmarried partners may disagree over paternal rights and responsibilities.
In these cases, either party can challenge paternity in court. While establishing paternity requires proof by a preponderance of the evidence (in other words, it simply must be more likely than not that the man is the child’s father), rebutting the presumption of paternity requires proof by clear and convincing evidence. This is a much higher standard, though it can also be satisfied through genetic testing.