LOS ANGELES, Dec. 5 – The tall, soft-spoken girl who gave police a major break in the Tate case is expected to testify voluntarily today before the County Grand Jury, which may indict her for multiple murder.

It was statements made to a jail cellmate by Susan Denise Atkins, 21, that confirmed a detective’s suspicions that the five Tate murders were done by the same persons who slew a Los Feliz couple a day later.

A full-scale investigation, then arrests and today’s grand jury inquiry followed.

Miss Atkins’ attorney said she would waive rights against self-incrimination to tell the grand jury how she took part in the two crimes.

He said he is gambling that her voluntary testimony might save her from the gas chamber.

The attorney, Richard Caballero, said Miss Atkins was temporarily insane at the time of the killings because she was acting under the hypnotic spell of Charles Manson, leader of a band of hate-oriented hippies.

“She will – tell the grand jury exactly what happened in both the Tate and LaBianca houses,” the attorney added. Members of Manson’s band are believed to have shot and stabbed Miss Tate and four others last Aug. 9 and stabbed Leno and Rosemary LaBianca the next night.

Dep. Dist. Attys. Aaron Stovitz and Vincent T. Bugliosi are expected to seek indictments against:

— Manson, 35, now in jail in Independence, Calif., on auto theft charges.
— Miss Atkins, now under indictment for a prior murder.
— Charles D. Watson, 24, now held at McKinney. Tex.. on a fugitive warrant from Los Angeles.
— Patricia Krenwinkel, 21, under arrest in Mobile, Ala., and resisting extradition to Los Angeles.
— Linda Kasabian, 20, five months pregnant, who returned voluntarily from New Hampshire and was arraigned on murder charges Thursday in a Los Angeles court.
— Steve Grogan, 18, also known as Clem Tufts.
— Miss Leslie Sankston, about 20.

Warrants for the arrest of Miss Atkins, Watson and Miss Krenwinkel were issued to hold them pending the grand jury inquiry. Grogan and Miss Sankston have been identified as members of Manson’s “Family” of wanderers.

Miss Atkins’ testimony will be a key part of the case against all seven, including herself.

What if she balks at the last minute?

The prosecution still has this evidence, it was learned:

The testimony of a motorcycle gang leader named Daniel Thomas DeCarlo, whose group once lived near where Manson’s hippies had a commune; the testimony of other members of the Family now held as material witnesses; the fact Manson had knowledge of the Tate home; at least one fingerprint found at the Tate home and the fact that Miss Atkins told a cellmate facts known only to someone who had been at the scene.

Miss Atkins was picked up in Death Valley in early October when local officers arrested 26 members of the Manson Family as suspects in a dunebuggy car theft ring.

She had been implicated by a former member of the Family in the July murder of Gary Hinman in Topanga Canyon. It is now believed that Hinman was also killed at Manson’s orders. She was brought here from Independence.

Police, meanwhile, had been investigating the Tate and LaBianca cases as separate crimes, despite startling similarities: hooded victims, messages written in blood, lack of motive, excessive brutality. Officers thought the LaBianca murders were the work of a “copy cat” after the Tate crime.

But Lt. Paul LePage, leader of the detectives on the LaBianca team, discovered evidence pointing to a link — and to Manson. The LAPD was investigating the Manson Family in early November.

In mid-November, at Sybil Brand Institute, Miss Atkins boasted of taking part in the Tate and LaBianca crimes to Shelly Joyce Nadell, 31, of North Hollywood, who was awaiting trial on a charge of having forged a drug prescription.

Miss Nadell told police what she had been told.

A full-scale investigation was ordered. By then, only one lieutenant and five men were still working on the Tate murders. Two lieutenants and 16 men were immediately assigned to the case. On Nov. 25, Los Angeles officers took a half dozen prisoners from Independence into custody on subpoenas from the grand jury.

Several will testify today as the jury takes up the complex, interlocking crimes in which seven persons died.

Stovitz and Bugliosi are expected to seek an eight-count indictment—one of conspiracy and seven of murder.

Evidence will be presented that all seven conspired to commit murder.

In addition, it is understood, seven counts of murder each will be sought against Manson, Miss Atkins, Watson, Miss Krenwinkel and Mrs. Kasabian.

Only two counts of murder — for the deaths of the LaBianca couple — will be asked against both Grogan and Miss Sankston.

Until 3 1/2 years ago, Miss Atkins’ attorney was a prosecutor who had obtained a total of five death penalties from juries during eight years in the district attorney’s office.

Caballero, 39, was appointed by a court to defend Miss Atkins. It was his experience in death-penalty cases which prompted him to suggest that she testify before the grand jury. He said he wanted to put her role in the slayings in its proper perspective:

“I feel that by taking this approach and having her present her story now, it will help show her state of mind to the grand jury — and especially to the prosecution in its later determination of whether to seek the death penalty.”

He said if she told the story of Manson’s sway over her at a trial, later, it might be open to the suggestion that it was fabricated.

Seeking the indictments will be two of Dist. Atty. Evelle J. Younger’s toughest prosecutors.

Stovitz, 45, a deputy district attorney for 18 years, has vast trial experience and is known for his cross-examination techniques.

Bugliosi, 33, just finished obtaining the convictions of a number of San Fernando Valley State College students for their roles in the seizure last year of two campus buildings.

Among those expected to be called before the grand jury will be Terry Melcher, son of actress Doris Day.

He is expected to testify that Manson knew the location of the secluded Tate estate in Benedict Canyon at 10050 Cielo Drive because he was acquainted with Melcher when the latter rented the house.

That was before Miss Tate and producer Roman Polanski rented the $200,000 home last February.

Polanski was in Europe at the time of the murders. Victims of the killings were Miss Tate; hairstylist Jay Sebring; Polish playboy Wojciech (Voityek) Frykowski; coffee heiress Abigail Folger and Steven Parent.

Much of the testimony is expected to dwell on Manson’s part in the cases.

He was reportedly not present when any of the murders took place. But, the investigation revealed, he ordered the bloody executions, and:

— In the case of the Tate murderers, supplied the .22-caliber revolver and bayonets used in the killings.
— Was actually first to enter the LaBianca home and personally bound the victims at gunpoint – and then left while others stayed behind to kill the couple with their own kitchen utensils.

Miss Atkins reportedly told Mrs. Nadell that the victims were marked for death by Manson, who believed the killings would release the souls of the victims, who would become slaves. His hatred was particularly directed at the affluent, she said.

The grand jury is expected to continue its investigation on Monday, and at that time will presumably return indictments.

Special security measures in the Hall of Justice were ordered by Superior Judge William H. Keene. Neither the prosecutors nor Caballero said they had requested them.

By DIAL TORGERSON and RON EINSTOSS