The country’s largest law enforcement agency is trying to combat COVID-19 vaccine hesitancy. But it’s also not tracking how many of its employees are vaccinated, calling that a personal choice.

About 30 CBP employees have died of the coronavirus and nearly 9,000 tested positive. But in testimony before the House Appropriations subcommittee on homeland security, the agency’s temporary head said it’s not tracking who’s getting the vaccine and is trying to encourage them to do so.

"It’s a personal choice so we’re going to continue to message it in anyway we can and I’m willing to work with you if you think you have some good ideas for us for how to continue to message the benefits of the vaccination to the workforce," Troy Miller told Democratic congresswoman Lauren Underwood who’d asked about vaccine rates among CBP’s 60,000 employees following the death of a Texas Border Patrol agent who died after delaying getting the vaccine.

Underwood said about 35% of CBP's workforce had been provided the vaccine through Veterans Affairs. But warned that of the remaining 65%, nobody was tracking whether they'd also vaccinated.

COVID-19 has been used as the reason for hardened measures at the border. Last summer, the head of CBP under former president Donald Trump said rapid border deportations, known as Title 42 expulsions, a title pulled from a CDC health measure, were helping to keep agents from being exposed.

Homeland Security employees have a history of refusing vaccinations. In 2016, ICE employees refused a measles vaccine during an outbreak at the Eloy Detention Center in Arizona.