Murder charge for Pleasanton driver in bike fatal

An 18-year-old man initially accused of vehicular manslaughter in connection with a crash that killed a bicyclist in Pleasanton was charged Wednesday with murder, in part because he had boasted about speeding on Twitter, authorities said.

Cody Hall of Pleasanton is now being held without bail in the death of Diana Hersevoort, 58, of Dublin, who was struck along with her husband on June 9 while pedaling north on busy Foothill Road, south of Golden Eagle Way.

An analysis of Hall's driving record and pattern - along with Twitter posts in which he talked about how fast he liked to drive - factored into upgrading the case to murder, authorities said.

An attorney for Hall was not immediately available for comment Wednesday.

Prosecutors have sought murder convictions in a number of Bay Area roadway deaths, often in cases where a motorist is intoxicated and has past convictions for drunken driving.

To prove second-degree murder, the government must show "implied malice," that a driver engaged in an intentional, unlawful act done with conscious disregard for the risk to human life.

According to police, Hall was driving north in a 2004 Dodge Neon and was traveling 83 mph in a 40-mph zone as he passed a vehicle at about 1 p.m. He lost control and collided with the couple, killing Hersevoort and injuring her husband, Johannes Hersevoort, 57.

Hall was also charged with reckless driving with serious injury for wounding Johannes Hersevoort.

While serving a search warrant in the case, police arrested Hall's father, Aaron Hall, 43, a twice-convicted felon, after finding two illegal assault rifles and thousands of rounds of ammunition in his home. He has been charged with numerous weapons violations.