40-5-237. District court paternity proceedings -- objection to tests -- additional tests -- expert's report -- admissibility of evidence. (1) In a matter referred to the district court, if an alleged father objects to the procedures for or the results of a paternity blood test, the alleged father shall file a written objection with the court within 20 days after service of the notice required by 40-5-236(3). The court shall order an additional paternity blood test upon the alleged father's advance payment for additional testing if a written objection is timely filed or at the request of the department. The alleged father's advance payment must be returned to the alleged father if the test does not produce evidence of the alleged father's paternity. An additional test must be performed by the same or another expert who is qualified in paternity blood testing. Failure of the alleged father to make a timely challenge is considered a waiver of any defense to the test results or test procedures, including the chain of custody.

(2) If an objection to the paternity blood test is not timely filed, the paternity blood test expert's completed and certified report of the results and conclusions of a paternity blood test is admissible as evidence without additional foundation testimony or other proof of authenticity and accuracy if the laboratory in which the expert performed the test is accredited for parentage testing by the American association of blood banks. Accreditation may be established by verified statement or reference to published sources. This subsection does not limit the right of a party to contest the identity of persons submitting to testing.

(3) In any hearing before the court or at trial, testimony relating to sexual intercourse of the mother with any person who has been excluded from consideration as a possible father of the child involved by the results of a paternity blood test is inadmissible in evidence.

(4) When a paternity blood test excludes an alleged father from possible paternity, the test is conclusive evidence of nonpaternity of the alleged father for all purposes in the district court.