MIAMI (CBSMiami) – A Miami-Dade Fire captain who was demoted after he made controversial comments about the Trayvon Martin case last year began pleading his case before an arbitrator Monday.

The post, made by then Captain Brian Beckman, said: “I and my coworkers could rewrite the book on whether our urban youths are victims of racist profiling or products of their failed, *expletive*, ignorant, pathetic welfare dependent excuses for parents.”

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Beckman made the post on the same day the shooter of Martin, George Zimmerman, was charged with second-degree murder in the case.

“This is the person that going to come to your house, he’s going to come my house and rescue my son?” asked retired Miami-Dade Corrections Officer Walter Clark.

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Both sides appeared before an arbitrator for the first day of hearings Monday. Beckman claimed he was misunderstood and that the post was copied from someone else who wrote it, though he has not shown evidence to support that.

Beckman also told CBS4 news partner the Miami Herald at the time that he was “a private citizen and has the same right to freely express an opinion on any subject that anyone else does.”

“To have someone take this type of stance is detrimental to my community,” said retired Miami-Dade Police Officer John Pace, Jr. “I can’t allow this to continue, to happen when we fought so hard to change things.”

Miami-Dade County Mayor Carlos Gimenez defended his decision Monday that the punishment fit in this case fit.

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“It’s a very offensive post,” Mayor Gimenez said. “It’s offensive to myself, my co-workers, and a large portion of Miami-Dade county.”