When execution is issued in any county and directed and delivered to the sheriff of another county, the sheriff after discharging all the duties required by law shall mail the execution to the clerk who issued the execution. On proof by the sheriff that the execution was mailed soon enough to have reached the clerk before the execution's expiration, the sheriff is not liable for any penalty if the execution does not reach the office in due time.
N.D.C.C. § 28-21-18