The fate of Terry L. Nichols will be decided by an Oklahoma jury, after a day of marathon closing arguments in which his lawyers tried to cast doubt on the state's evidence and lay the blame for the Oklahoma City bombing on Timothy J. McVeigh and others.

"This is a case about manipulation, betrayal and overreaching," defense attorney Barbara Bergman said. "People who are still unknown assisted Timothy McVeigh."

Bergman spent 90 minutes Tuesday outlining deficiencies in the state's scientific evidence in the April 19, 1995, blast that ripped open the Alfred P. Murrah Federal Building and killed 168 people. She raised questions about whether the two-ton bomb, stuffed into a Ryder truck, was really built from fertilizer and fuel, components the state alleged Nichols helped purchase and hide using aliases.

Nichols is serving a life term on a federal conviction for the deaths of eight law enforcement officials in the blast. McVeigh was executed for the bombing. The state opted to try Nichols again, in hopes of getting the death penalty, using much of the same evidence presented in 1997.

Nichols is facing 161 murder counts for the other victims, including a fetus. The jury may consider only first-degree murder or not guilty verdicts.

Defense attorney Brian Hermanson took pains to distance Nichols from McVeigh during the months leading up to the blast and suggested McVeigh kept Nichols in the dark -- and even planted evidence to set up Nichols.

But in her rebuttal, assistant district attorney Sandra Elliott told jurors, "For you to believe that Mr. Nichols is not involved in the conspiracy, you would have to believe so many coincidences falling down around Mr. Nichols that it's unimaginable."

Bergman lambasted the testimony of an FBI fingerprint expert who testified that Nichols's palm prints were on a map of Oklahoma City. On cross examination, however, the FBI agent said that he had been mistaken and that there were no such prints. "He was just plain wrong," Bergman said. "He testified under oath in a capital case about palm prints that don't exist."