He said investigators were also talking with her colleagues at work.
After investigators talked with him, they decided that there was nothing they could do and closed the case, prosecutors said.
A private investigator was checking into your history-we talked to your mother about it.
County officials said investigators had talked to three of the eight people who were on the ride around 4 p.m. on Wednesday.
The investigator talked to the local officials involved, but asked to remain anonymous because of restrictions on speaking with reporters.
He said the investigators would talk to the former hostages, most of whom are former State Department officials.
During the city inquiry, investigators talked to people listed as contributors to the campaign and questioned them about what they had agreed to contribute.
Several investigators last week talked more openly about their concern that some pieces would never be found.
After the recipients became ill, investigators talked with the donor's wife, who said that he had a fever before the accident.
Mr. Fitzgerald died last year before investigators could talk to him.