Dr. Cyril H. Wecht's former top secretary at the Allegheny County coroner's office ended a seven-day marathon of testimony in his federal fraud trial, as days of pent-up stress gave way to sniffles and tears on the witness stand.

For days, prosecutors have used Eileen Young's testimony to back up charges of mail and wire fraud against the former coroner.

Testifying under immunity, Ms. Young has detailed how she routinely handled the paperwork for Dr. Wecht's private consultation and autopsy business from the coroner's office, sending faxes, taking calls and doing billing and correspondence.

Yesterday, Assistant U.S. Attorney James Wilson chipped away at his own witness's credibility and memory, challenging her recollections of testimony before a federal grand jury and even during cross-examination from days earlier.

Ms. Young insisted that she disguised her handwriting on fake limousine bills to Dr. Wecht's private clients -- to make it appear the round-trip portions were filled out at different times by different people -- because her predecessor and close friend Maribeth Blettner told her that's what she did.

But Mr. Wilson questioned Ms. Young's memory and showed jurors a dozen limo invoices filled out presumably by Ms. Blettner, none of which had distinctly different handwriting. The intimation was that Dr. Wecht, not Ms. Blettner, told her to defraud his clients.

"Miss Young, it wasn't Maribeth Blettner you were trying to protect, was it?" Mr. Wilson said.

"Oh yes I was," she shot back. "She's the one who gave me these [blank limo] receipts."

Mr. Wilson used Ms. Young to address numerous points made by defense attorney Mark Rush. The most important: Exhibits presented by Mr. Rush indicating that 27 of the government's 41 charges against Dr. Wecht stemmed from faxes and mailings that took Ms. Young less than three hours to prepare over a four-year period. The total cost to taxpayers: $3.96.

Mr. Wilson tried to turn that line of reasoning on its head.

"Let's use Count 1," Mr. Wilson said. "You took a fax that cost 23 cents, and it brought back $3,000 in fees."

Mr. Wilson was referring to an invoice Ms. Young sent to Exxon-Mobil for a $3,000 honorarium for a speaking engagement by Dr. Wecht in 2002. That fax cost 23 cents to send, according to county phone records.

Mr. Rush called that logic an "unfair analogy," saying that it wasn't the fax that brought in $3,000, but rather Dr. Wecht's lifetime of experience.

The trial continues today with Bryan Hinds, an accountant for Dr. Wecht's private business, on the stand.