Olathe ? The lead lawyer for serial-murder suspect John E. Robinson on Thursday asked to withdraw from the case because of a conflict of interest.

One of Bob L. Thomas’ previous clients, who was in jail with Robinson, could be called as a witness because he says Robinson told him crime details no one else knew, according to documents filed in Johnson County District Court.

Thomas’ request could lead to a second delay in Robinson’s trial, scheduled for September.

Two experienced death-penalty defense lawyers who were appointed to help Thomas asked District Judge John Anderson III to postpone the trial because they will have to bear Thomas’ work load if he leaves.

Dist. Atty. Paul Morrison said he wanted to file written objections to the motions, so the judge said he would take up the issues at a previously scheduled hearing next Thursday.

Robinson of Olathe faces capital murder charges in the deaths of two women whose bodies were found in June 2000 in metal barrels on property he owned in Linn County.

Robinson also is charged in Missouri with killing three women whose bodies were found in barrels in Cass County.

The conflict has to do with Thomas’ former client, Marvin Ray. Ray apparently wrote prosecutors, saying he had information about the case.

Thomas, who was a first-year lawyer when Robinson hired him last year, said after the hearing that he would like to stay on the case. But he said his responsibility to withhold protected information about the former client would keep him from properly representing Robinson.

“If I thought there was any way I could ethically stay on this case as John Robinson’s attorney, I would,” Thomas said.

Ray, 34, was in the Johnson County Jail with Robinson for about one month last summer. He had been placed on probation after pleading guilty to felony theft in August 2000, according to Johnson County District Court records. He was transferred in August to the Kansas Department of Corrections.

In a letter to prosecutors last summer, Ray laid out his claim to have information provided by Robinson.

Authorities searched Ray’s cell and found a three-page, hand-written letter in which Ray contends that he helped a woman and a man not Robinson take the bodies of two women from Topeka to a farm near La Cygne in exchange for 2 pounds of crack cocaine.