Cerf's decision supersedes the ruling last month by Administrative Law Judge Jeff S. Masin that Carr deserved to lose his tenured protection and be terminated and that his "ability to serve as a proper example for students has been severely compromised."
Masin also said allowing him to return "would be grossly unfair" to Carr's ex-wife, a teacher at the high school.
Both rulings note that in February, Carr had another episode of misconduct involving his ex-wife. In that incident - which, as with the bag of feces he put on his ex-wife's windshield - he denied and then eventually admitted, he put an article about bipolar disorder in his ex-wife's school mailbox.
At the time, Carr, recently divorced, was given an informal warning by his superiors.
Cerf said in his ruling he had no evidence Carr would repeat his past poor judgment. Carr, he wrote, said he had been in a "bad place" last year. Since then, Carr has received and is still receiving counseling, Cerf wrote.
Carr, athletic director for 23 years who was also the district's health and physical education supervisor, had received positive reviews, Cerf said. He joined the district in 1974 and was also a teacher.
The Haddon Township Board of Education voted July 19 in favor of terminating Carr.
Superintendent Nancy Ward declined to comment Friday. Carr and his former wife could not be reached.
Cerf's decision can be appealed.
Contact Rita Giordano at 856-779-3893, firstname.lastname@example.org, or follow on Twitter @ritagiordano.