VISTA, Calif. -- A motorist accused of being under the influence of alcohol and methamphetamine when she drove into oncoming traffic on state Route 76, killing two couples, pleaded not guilty Thursday to four counts of second-degree murder.

Deanna Fridley, 24, was originally thought to be a passenger in the SUV that smashed into the victims' car on Dec. 14, 2007, but it was later determined that she was the driver.

Her passenger, Anthony Boles, pleaded guilty to drug charges and has already been sentenced.

After a preliminary hearing in May, Fridley was ordered to stand trial on charges on four counts of gross vehicular manslaughter while intoxicated, including allegations that her actions caused great bodily injury to the victims. Fridley is also charged with driving on a suspended license.

She was arraigned Thursday on the second-degree murder counts, which were subsequently added to the list of charges.

Killed in the crash were Escondido residents Jesus DeSantiago, 45; his wife, Lina, 46; and Luis Baez, 51; and his wife, Rubi, 46, of Vista.

Judge Daniel Goldstein confirmed the defendant's trial date of Feb. 17. A readiness conference is scheduled for Nov. 20.