Vt. Stat. tit. 15 § 207
Other evidence shall not be required to prove the civil marriage of the husband and wife, or that the respondent is the father or mother or stepfather or stepmother of the child, than is or shall be required to prove such facts in a civil action. In a prosecution under this subchapter, any existing statute or rule of law prohibiting the disclosure of confidential communications between husband and wife shall not apply, and both husband and wife shall be competent witnesses to testify against each other to any and all relevant matters, including the fact of the civil marriage and the parentage of the child; provided that neither shall be compelled to give self-incriminating evidence. Proof of the desertion of the husband or wife or child in destitute circumstances or of neglect or refusal to provide for the support and maintenance of the husband, wife, or child shall be prima facie evidence that the desertion, neglect, or refusal is willful.
15 V.S.A. § 207