BRENTWOOD (KPIX 5) — A senior at Liberty High in Brentwood wanted to show off his military pride at his graduation ceremony by wearing his army uniform, but school insisted he cover it up.

That’s a violation of military uniform code.

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Harland Fletcher says the proudest achievement of his life was to wear his army dress blues.

“I talked to my counselor the day before practice,” he said.

But, when he showed up to bask in the pomp and circumstance — he was denied.

“’No, you can’t walk in that’ and I asked ‘why’ and he said ‘that’s not the graduation uniform’,” says Fletcher, remembering the conversation.

So he asked again.

“They said they had an extra cap and gown and I said, ‘I’m sorry, i can’t do that. That’s defacing the uniform. That’s against the uniform policy.’” says Fletcher.

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He told them he was not going to participate and walked away.

According to the uniform code of Military Justice, covering a uniform could have made the 18-year-old subject to a court martial.

So, instead of crossing the stage clutching his diploma before heading to Advanced Individual Training at Fort Sam Houston in San Antonio, Fletcher walked out.

The Liberty Union High School District issued a statement to KPIX 5 Saturday, saying they were wrong and offering this apology:

“No slight was meant to Harland nor to the US Army. In fact with a little prior notification I’m sure Principal Walsh and the site administration would’ve come to this conclusion before the ceremony.”

“I honestly feel like you can apologize all you really want, but in the moment you should’ve already known,” says Fletcher.

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For him, the apology is not enough.