An accused drunken driver with a prior conviction pleaded not guilty to a DWI hit-and-run that left three people injured in April.

Investigators say Peter Ethier, 26, of Westhampton Beach, was speeding on Sunrise Highway near Speonk-Riverhead Road when he rear-ended a car. Police say he took off, but was later arrested.

Ethier faces charges including DWI, leaving the scene and failure to install an interlock device in his car as ordered by the court after a DWI conviction in January.

Prosecutors say he was driving his parents' car the night of the April crash.

Ethier's attorney told News 12 Long Island that it is not clear if his client was even operating the vehicle at the time of the crash, saying there was no eyewitness.

The 26-year-old is being held on $150,000 bail.

Richard Mallow, with the anti-drunken driving group MADD, says this case highlights a major problem in the current legal system. Interlock systems are often ordered by the court, but Mallow says only 5 percent of people who should have one actually install it.

MADD says another solution would be to have all new cars built with technology that won't allow it to start if the driver is intoxicated.

"We can end drunk driving by 2025 with this technology," says Mallow.