PORTLAND – A Portland man accused of killing a woman by pushing her off a bridge has been sent to prison for 20 years.

A Cumberland County Superior Court judge on Tuesday handed Everett Ashby a 35-year sentence with 15 years suspended. Ashby pleaded guilty to a manslaughter charge in March. Under the plea agreement, he was to be sentenced to no more than 20 years in prison and no less than 15 years.

Ashby had been charged with both murder and manslaughter in the 1998 death of 24-year-old Amy Gaines of Westbrook. As a consequence of his plea, the murder charge was dropped.

Gaines went off Cousins Island Bridge in the early morning hours of Aug. 21. Her body was found floating near the bridge the next day.

Five days after the incident, Ashby went to the Westbrook police station and gave an evolving explanation of what happened, according to police. He told detectives he met Gaines in a Westbrook bar and offered to drive her home. At first Ashby said he dropped Gaines off after she became unruly and never saw her again, police said.

Police said that upon further questioning, Ashby told them he took Gaines to Cousins Island, thinking she wanted money for sex. He said a fight broke out between them on the bridge, and that when he pushed her, she flipped backward over the rail, according to police.