When a shooter opened fire at Marjory Stoneman Douglas High School in Parkland, Florida, last month, sheriff's deputy Scot Peterson, who was on duty as the school's resource officer, reportedly failed to enter the building as 17 people died — but that's not why the police union won't be defending him.

According to Jeff Bell, president of the Broward County Sheriff's Deputies Association, the union will not be stepping up to help Peterson, not due to his conduct but because he doesn't pay the union any money, Reason.com reported.

"From a legal standpoint, we say he was not a 'dues-paying member," Bell said, according to Reason.com. "If he was a dues-paying member, I would certainly have a problem with how we are trying him in the public and not giving him his due process. But because he's not a dues-paying member and I don't have to represent him? Whatever happens, happens."

Under Florida's public sector union laws, Peterson is not required to financially support Bell's union, but he's also not legally free to associate with a different bargaining unit instead. While the law enforcement veteran of 32 years is still covered by collective bargaining agreements signed by Broward County Sheriff's Deputies Association, the union didn't act on his behalf when he indicated prior to his resignation that was upset that his employer suspended him following the tragedy — and they won't be coming to his rescue should he face any legal repercussions for his inaction at the high school.

Peterson may be eligible to collect a pension of at least $52,000 and is supposed to have half of his health insurance premiums covered the Broward County Sheriff's Office for life. Although he claims he thought the shooting was taking place outside the school, his failure to enter the building and confront the shooter could still lead to his facing an investigation and ending up in civil court. Either way, the Broward County Sheriff's Deputies Association won't be involved.

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"If the sheriff's office decides not to, say for example, they decide you know what, we're not going to give you your payouts and we're not going to give you your insurance or whatever, I'm still not doing anything for him," Bell said. "So, he doesn't have the right to file a grievance–well, he can do it as an individual, but when he gets to the level of arbitration, we're not covering that. If he has any lawsuits, we're not covering that. Administrative hearings or civil hearings, we're not covering that."

Only "dues-paying members" get that level of protection, he added.