David Robert Franz, 29, is expected to get a 15-year prison term at his Feb. 24 sentencing.
Franz, who was found guilty of first-and-second degree arson on Tuesday, will serve the first half of his sentence under Oregon's Measure 11, which does not allow him to attend prison programs or earn time off for good behavior. He will qualify for programs and time off for the last half, according to court records.
Franz, who had been arrested 91 times since 1996, mostly for drug and theft crimes, was an early suspect in the arsons, police said last year.
Franz and two others were arrested in 1995 for a series of Springfield fires that burned an office building, a grocery store, two trash bins, a newspaper box and a car. In that case, he pleaded guilty to a burglary charge and served probation. A charge of conspiring to commit arson was dropped, court records show.
Franz was living in downtown Springfield last year when 12 fires tied to him were set in his neighborhood. When Franz moved east, fires started breaking out in that neighborhood, deputy fire marshal Brian Parmelee said after Franz's arrest.
Investigators got a break when a Lane County sheriff's deputy investigating a burglary talked with some people who mentioned Franz as a possible suspect in the arsons.
Franz, who was frequently released from the Lane County Jail because of overcrowding, became a poster child for proponents of Springfield's successful bond measure for a new police building and court in the November election.
The measure also authorizes construction of a 100-bed city jail if Springfield's leaders choose to pay operating costs.