> How does that relate to ATM fraud?

“In 1984, the US Congress passed the Comprehensive Crime Control Act, which extended the Secret Service's jurisdiction over credit card fraud and computer fraud.”

https://en.m.wikipedia.org/wiki/United_States_Secret_Service...

The Secret Service is the law enforcement branch of the Treasury Department, like the FBI is the law enforcement branch of the Justice Department and ICE is of the Dept of Homeland Security. The President-protecting stuff is the weird part of their duties, not the other way around :)