Driver arrested on suspicion of DUI in rollover injury collision, Merced police say

A man has been arrested on suspicion of DUI after a multi-vehicle collision involving a rollover in Merced on Wednesday, according to police.

Just after 9 p.m, officers responded to the the area of G Street and 23rd Street for a report of a rollover collision, according to Merced Police Sgt. Nathan McKinnon. Officers found a 2023 Jeep that had rolled over, a 2009 Nissan Altima with major front-end damage and a 2018 Subaru with rear-end damage.

According to police, all three vehicles were traveling north on G Street when the collision occurred. McKinnon said it appears the Nissan struck the Jeep causing it to collide with the Subaru. At some point, the Jeep overturned.

Police said the Jeep was driven by a 29-year-old Merced woman who was transported to a trauma center for treatment of moderate injuries. The Subaru was driven by a 45-year-old Merced woman with two passengers. Police said none of the Subaru’s occupants suffered injuries.

Authorities said officers noticed signs and symptoms that the driver of the Nissan, identified as 30-year-old Ralph Guerrero of Merced, was under the influence. Officers on scene reported noticing an odor of alcohol, according to McKinnon. Police said several witnesses provided statements to officers.

“He was driving well over the posted speed limit,” McKinnon said.

Guerrero was arrested and booked into Merced County Jail on suspicion of felony driving under the influence causing bodily injury, driving under the influence of at least .08 blood-alcohol level causing bodily injury, transportation of narcotics and misdemeanor possession of a narcotic controlled substance, according to jail records.

Anyone with information regarding the incident is asked to contact Officer Calcagno at 209-388-7718 or by email at