On 13 June 1989 , Bartels wrote a letter on Zvonko Bušić 's behalf to the U.S. Parole Commission , in which he stated that the death of the police officer was partly due to the police 's negligence and that he had no objection to Bušić 's release .
On June 13 , 1989 , Bartels wrote a letter-opinion to the U.S. Parole Commission , in which he stated that the death of the police officer was partly due to the police 's negligence and that he had no recommendation to the Commission nor objection to Bušić 's release .