The Senate Ethics Committee Tuesday agreed not to require Sen. Alan Cranston to undergo public questioning in the Keating Five case after his lawyer said he is too ill from cancer therapy to appear.

The panel voted unanimously that it would not compel Cranston's appearance, either in person or by televised hookup.William Taylor III, Cranston's defense attorney in the Keating Five case, said Cranston was not strong enough to undergo even a videotaped questioning and that the senator waived his rights to be examined in public.

He said the California Democrat's earlier statements to the panel in private sessions would have to stand as Cranston's defense against ethics allegations.

"It is the physician's view that participating in any format of live testimony in this matter would not be consistent with what is necessary for Senator Cranston's treatment," Taylor said.

Cranston is one of five senators under investigation by the ethics panel for allegations they improperly intervened with federal regulators on behalf of a major financial contributor, failed savings and loan owner Charles H. Keating Jr.

Taylor's request came as the panel was questioning Sen. Donald Riegle, D-Mich., the third of the five senators to face public examination.

Sen. Warren Rudman, R-N.H., vice chairman of the ethics panel, said he believed Cranston had already answered all important factual questions. The motion he proposed, and the committee adopted, said the panel could pose written questions as needed and that Cranston would be expected to provide prompt and sworn written responses.

Taylor said Cranston had completed a seven-week course of radiation therapy for his prostate cancer and has suffered expected debilitating side effects. He said Cranston's doctors have decided to follow that therapy with radioactive implants, to be applied through surgery near his malignant tumor later this month.

He said Cranston needs to recuperate and regain strength before undergoing that surgery.

Taylor said he could not predict when Cranston could provide testimony in public, but that Cranston hopes to be back to his Senate duties before the end of February.

Earlier, Riegle told the Ethics Committee he can't recall discussions with Keating about the S&L owner's problems with federal regulators.