So, based on the article, the marijuana was evidence. So I'm not entirely sure if possession charges would apply here.
"failing to file 37 reports, one of them the report of the marijuana he picked up at the UPS store. When questioned, Avila told investigators that he used 2 pounds of the marijuana to train his police dog"
he is well aware of all the laws he broke. he was waiting it out and thinking he would get away with it.
that is possession as well.