Santa Ana, California - An Aliso Viejo man pleaded guilty to federal charges stemming from a vehicular assault that severely injured an employee of U.S. Customs and Border Protection at the federal building in Laguna Niguel.

Geoffrey Donald Rickner, 48, pleaded guilty to one count of assault on a federal employee by use of a dangerous and deadly weapon and inflicting bodily injury, a felony offense that carries a statutory maximum sentence of 20 years in federal prison.

Rickner admitted driving his Mercedes-Benz sedan into CBP Security Specialist Jose Gutierrez on March 3, 2016 at the Chet Holifield Federal Building, which is commonly known as the Ziggurat Building. Mr. Gutierrez, who was in a well-marked crosswalk and wearing his federal employee identification card, suffered permanent and life-threatening injuries – including head trauma, broken ribs, internal bleeding and badly damaged legs – that put him in the hospital for nearly three weeks and continue to cause him pain and physical impairment.

When Rickner struck Mr. Gutierrez, the vehicle was travelling at such a high rate of speed that it continued traveling into the Ziggurat, going through a metal garage door, and stopping only when it struck a concrete wall inside the building.

Rickner had been behaving suspiciously in the hours leading up to the assault on Mr. Gutierrez, prompting building security personnel at one point to detain him, during which he made comments about owing money to the Internal Revenue Service, according to documents previously filed in this case.

Rickner pleaded guilty before U.S. District Judge James V. Selna, who scheduled a sentencing hearing on October 7.

The investigation in this case is being conducted by the FBI and the U.S. Treasury Inspector General for Tax Administration.

This matter is being prosecuted by Assistant United States Attorney Robert J. Keenan of the Santa Ana Branch Office.