SAN FRANCISCO » An attorney in the case of a Northern California girl held captive in a backyard compound for 18 years said Monday he expects defendant Phillip Garrido to plead guilty to all charges and his wife to go to trial unless she gets a better plea deal.

Lawyer Stephen Tapson, who represents defendant Nancy Garrido, said her husband will likely make the guilty plea on Thursday at a pretrial conference.

“Unless some hitch develops, I’m 99 percent sure Phil will ‘plead to the sheet’ and possibly be sentenced at the same time if (the) judge has figured out the correct number of hundreds of years,” Tapson said, explaining he learned of the development from discussions with a lawyer for Phillip Garrido and the prosecutor in the case.

Public defender Susan Gellman, who represents Phillip Garrido, did not immediately return a phone message seeking comment. El Dorado County District Attorney Vern Pierson declined to comment.

The Garridos are each charged with 18 felony counts of false imprisonment, rape and child pornography. Nancy Garrido has pleaded not guilty. Phillip Garrido, a convicted sex offender, has not yet entered a plea.

They are accused of kidnapping 11-year-old Jaycee Dugard from outside her South Lake Tahoe home in 1991.

If convicted on all counts, the maximum sentence for Nancy Garrido would be 181 years to life, while Phillip Garrido could get 431 years to life, according to El Dorado County Deputy District Attorney James Clinchard.

The Garridos held Dugard and her two daughters fathered by Phillip Garrido captive until their arrest in August 2009, prosecutors said.

Dugard’s case revealed problems with California’s system for monitoring convicted sex offenders after it was determined that parole agents had missed numerous clues and chances to find her.

Dugard, now 30, received a $20 million settlement under which the state acknowledged repeated mistakes were made by parole agents responsible for monitoring Phillip Garrido. The state has since increased monitoring of sex offenders.

Attorneys on all sides have said they wanted to avoid trial so Dugard did not have to testify, but that now seems unlikely in Nancy Garrido’s case, Tapson said.

“Nancy never wanted her to have to testify,” said Tapson. “She said that long ago and wanted a reasonable sentence, which the district attorney has rejected now.”

Dugard has said through her spokesman that she would be willing to testify if the cases went to trial.

Tapson said the initial offer to his 55-year-old client was 40 to 50 years in prison, which meant she could likely get out after 30 years. Tapson said the district attorney had increased that offer to 183 years to life.

Prosecutor Pierson has said Tapson’s comments asking for compassion for Nancy Garrido were offensive.

Phillip Garrido’s maximum sentence in the case would be 563 years to life.

Associated Press Writers Lisa Leff and Marcus Wohlsen contributed to this report.