District Attorney Jill Ravitch's office announced Monday it will seek the death penalty against Mark Cappello, who is accused of the execution-style murder of three men in Forestville in February 2013.

It's the first time since 1995 that a Sonoma County District Attorney has sought the death penalty in a murder trial.

"It's fair to say any time a decision as serious it this is made, it must be thoughtful and thoroughly reviewed," said Ravitch. "We carefully considered many factors in coming to this difficult conclusion."

Cappello, 47, and Odin Dywer, 39, both of Colorado and Francis Dwyer, 66, of New Mexico, have been charged with the Feb. 5. 2013, slayings of Todd Klarkowski, 43, of Boulder, Colo.; Richard Lewin, 46, of Huntington, N.Y.; and Raleigh Butler, 24, formerly of Sebastopol.

The trial, scheduled to begin on May 23, had been delayed in part as Ravitch determined whether to seek the death penalty on Cappello, who is accused of shooting the three victims during a marijuana transaction.

The three defendants will be in court Tuesday morning for a pre-trial confirmation hearing.

It remains unclear whether the three defendants all will be tried. Francis Dwyer has offered to settle his case for undisclosed terms.

During a preliminary hearing, witnesses testified Cappello and Odin Dwyer met the victims at a house on Ross State Road where Klarkowski and Lewin were buying 100 pounds of marijuana which they were planning to ship to the East Coast.

The defendants were allegedly the drivers. But after the pot was packaged for transport, Cappello pulled a gun and shot the three victims, Odin Dwyer told police.

The three suspects were arrested later that month at different locations.

Ravitch said pursuing the death penalty against Cappello was based on a number of factors, including his background, his prior crimes, the nature of the murder and that the crime was for financial gain. But, she said, it was not set in stone.

"This is an ongoing investigation," she said. "In the event that mitigating factors arise, we will take another look at it. It's a decision that is subject to review throughout this process."

Cappello's attorney, Michael Meehan, did not return a phone call seeking comment.

Robert Walter Scully was the last person sentenced to death in Sonoma County when he was sent to death row in 1997 for the March 29, 1995, murder of Sonoma County Deputy Sheriff Frank Trejo. Richard Allen Davis has been on death row since 1996 for the murder of Polly Klass, 12, of Petaluma in 1993.

Twenty-four people were sentenced to death in California last year and four so far in 2014, according to statistics released by the state.

California's death row is the largest in the nation at 741. The last person executed in the state was Clarence Ray Allen who received a lethal injection on Jan. 17, 2006.

You can reach Staff Writer Elizabeth M. Cosin at 521-5276 or elizabeth.cosin@pressdemocrat.com.