Alaska Stat. § 11.56.765

(a) A person, other than the victim, commits the crime of failure to report a violent crime committed against a child if the person (1) witnesses what the person knows or reasonably should know is (A) the murder or attempted murder of a child by another;

(B) the kidnapping or attempted kidnapping of a child by another;

(C) the sexual penetration or attempted sexual penetration by another (i) of a child without consent of the child;

(ii) of a child that is mentally incapable;

(iii) of a child that is incapacitated; or

(iv) of a child that is unaware that a sexual act is being committed; or

(D) the assault of a child by another causing serious physical injury to the child;

(2) knows or reasonably should know that the child is under 16 years of age; and

(3) does not in a timely manner report that crime to a peace officer or law enforcement agency.

(b) In a prosecution under this section, it is an affirmative defense that the defendant (1) did not report in a timely manner because the defendant reasonably believed that doing so would have exposed the defendant or others to a substantial risk of physical injury; or

(2) acted to stop the commission of the crime and stopped (A) the commission of the crime; or

(B) the completion of the crime being attempted.

(c) In this section, (1) “incapacitated” has the meaning given in AS 11.41.470 ;

(2) “mentally incapable” has the meaning given in AS 11.41.470 ;

(3) “sexual act” has the meaning given in AS 11.41.470 ;

(4) “without consent” has the meaning given in AS 11.41.470 .

(d) Failure to report a violent crime committed against a child is a class A misdemeanor.