Vice President and General Counsel Margaret H. Marshall acknowledged in an interview last week that security guards participating in an investigation of their unit were not informed beforehand of their right to be accompanied by an attorney during interviews.

Marshall had refused to comment on the investigation for the last six months, other than to say it was continuing.

Several of the 36 current guards interviewed in the probe, which was conducted by Marshall's former law firm, Choate, Hall & Stewart, have complained that they were not given advance notice that they could be accompanied.

Many guards said they would have liked to take advantage of the opportunity to have a representative accompany them, but by the time of the interview, it was too late.

"In the course of the interview, they were told they could have anyone present," Marshall said last week.

A report detailing the findings of the Choate, Hall & Stewart investigation was released last week by Marshall. The report found that there was no discrimination or harassment on the basis of race, gender or national origin in the security guard unit of the Harvard Police Department.

Eleven former and current security employees have charged that they were treated unfairly by security officials. The report blamed guards, a union steward, the student press, fiscal constraints and management weakness for the perception by some employees of discrimination. And it offered 14 recommendations "to ensure for the guard service a work environment of respect, professionalism and communication among guards, supervisors and managers."

But the report has not stifled criticism of Marshall's investigation.

Guards have said that the unannounced appearance of Choate, Hall & Stewart attorney Karen L. Cartotto, who joined investigator James A. Ring shortly into the interviewing process, was startling and upsetting. Neither Cartotto's presence nor the right to a representative was mentioned in Marshall's January letter to all guards offering them the opportunity to be interviewed as part of the investigation.

Marshall would not comment on Cartotto's presence or other aspects of the probe.

"I'm not going to comment on how our investigation was conducted," Marshall said last week.

She said again this Wednesday that she would not comment, "at least this week."

In last week's interview, Marshall repeatedly emphasized that the investigation was thorough because all current and some former guards had been offered the opportunity to be interviewed.

"What I did was to make sure everyone had an opportunity to be interviewed," Marshall said.

But two guards who have charged discrimination--current guard Steven Thompson and former guard Rolando Diaz--said this week they never received letters requesting interviews.

President Neil L. Rudenstine said Wednesday he had read the report and would comment on it after he had spoken to Marshall