Prosecutors asked for more time Thursday to consider charges against a Rohnert Park man suspected of using his cellphone and driving under the influence of marijuana in a crash that killed two Santa Rosa women.

Nicholas Tognozzi, 30, appeared before Judge Dana Simonds, who ordered him to return to court May 14 for the possible filing of formal charges. He remains free on $100,000 bail.

Tognozzi was arrested March 15 after rear-ending a car carrying four adults on Highway 12 near Farmers Lane. Sharon Hufford, 74, and her daughter-in-law, Sue Hufford, 53, died instantly.

Police believe Tognozzi looked down at his phone to read a text message moments before the crash. A drug recognition officer evaluated Tognozzi and concluded he had been using marijuana.

Prosecutors said they were awaiting additional evidence before deciding how to proceed. The results of urine testing by the state Department of Justice were not available.