The actress said that one of the reasons she loves starring in the CBS crime drama is because she's always been fascinated with the police.
"I'm super-obsessed with law enforcement. I'm what you'd call a cop fan," Perrette joked in an interview with Parade.
She further explained: "I have so much respect for first responders. I get excited meeting police officers the way other people do meeting celebrities."
In December, Perrette got engaged to her boyfriend Thomas Arklie, but said that she won't walk down the aisle until gay marriage is legalised in California.
NCIS airs Tuesdays at 8/7c on CBS.
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