A judicial commission investigating alleged abuses of power by former Indian Prime Minister Indira Gandhi and some of her senior aides has evidence that is expected to lead to her re-arrest.

It reputedly includes evidence that Gandhi blocked an inquiry into allegations that her son, Sanjay, illegally imported equipment from his controversial automobile manufacturing company and intimidated civil servants who were gathering the information.

The government, humiliated when Gandhi was released from custody after her arrest on corruption charges two weeks ago, is determined to build its evidence more firmly before moving against her again. According to a source close to the investigations, her re-arrest is not expected for another six weeks or so.

Meanwhile, this source said, "evidence is pouring in against her. We're picking and choosing our cases carefully and concentrating on these with the hardest evidence."

The atmosphere surrounding the proceedings against the former prime minister improved this weekend when Gandhi's Congress Party rejected an effort to make her its president. She insisted she was not interested in the office, but in a speech to a party group last night she bitterly attacked the current Congress president, K. Brahmananda Reddy.

The Congress gathering condemned Gandhi's arrest, but it refused to force Reddy out of office after several prominent party members warned against efforts by Gandhi supporters to return the party leadership to a "cult of personality" centered on her.

This division in the Congress Party between supporters and opponents of the former prime minister has encouraged the ruling People's Party, itself a shaky coalition. There had been rumors that the government was backing away from re-arresting Gandhi after her earlier arrest raised a public outcry. These rumors have largely subsided.

Most of the evidence gathered by the special commission, headed by former Supreme Court Chief Justice J.C. Shah, has not yet been made public, but, material obtained by The Washington Post in one case reveals that Gandhi used her power to intimidate four civil servants who were collecting information on Sanjay and to halt their inquiry.

According to the case compiled by the commission, the four had been ordered by their superiors to check into allegations that Sanjay's automobile manufacturing company, Maruti, Ltd., illegally imported equipment without a license.

The allegation had been made in Parliament in April 1975, two months before Gandhi imposed a "national emergency." As part of their inquiry, the four officials contacted the Maruti firm and one of its associates, Batliboi Co. According to the evidence, the companies immediately complained.

On April 15 the commission's evidence indicates, Gandhi's private secretary, A.S. Dhawan, telephoned two of the civil servants and "forbade them from collecting any further information" about Maruti.

On the same day, Gandhi summoned Heavy Insustries Minister T.A. Pai to her home. According to Pai'ss testimony, she was "completely upset and furious." Then, Pai said, Gandhi telephoned the director of the Central Bureau of Investigation, India's equivalent of FBI, and ordered him to make inquires into possible criminal and corruption charges against the four men.

The investigations began that night. The next day, the director of the bureau ordered that a charge be brought against them for allegedly owning more property than their salaries would allow.

Their homes were searched two days later. In one, police found more liquor than was permitted under the law. A court later dismissed this as irrelevant. No other evidence could be established against any of the four.

Nevertheless, allegedly spurred Gandhi's orders, the bureau pressed its investigation. One of the men, P.S. Bhatnagar, was suspended from his job. Another, L.R. Cavle, was ordered transferred from New Delhi to an inferior job in Madras.

Cavle refused the transfer and protested to his superior. As a result, he was placed under surveillance and the police began "verification" procedures against him. Cavle cracked under the pressure and resigned his civil service job, the commission's findings show.

According to the commission's report, neither Cavle nor his wife were able to get new jobs. Even when the police dropped its case against him for lack of evidence, he was not rehired by the State Trading Corporation.

The report concludes that the four were "harassed and criminal cases were instituted against them, apparently, because they were instrumental in collecting information, though legitimately and in the normal discharge of their official duty . . . The allegations of possession of disproportionate assets on the basis of which the CBI registered cases against these four officials and searched their premises, could not ultimately be proved and were dropped."

The commission suspended its hearings on Oct. 4, the day a New Delhi judge released Gandhi. Informed sources said the commission's chairman, Shah, was angered that the government moved before the commission had completed its investigations.

After meeting with Prime Minister Morarji Desai, however, Shah announced that the commission would resume its work on Oct. 26.

Gandhi, who has been questioned twice, is expected to be summoned before the commission again. A source close to the commission said written evidence against the former prime minister has been compiled in five cases and oral evidence has been submitted in several more.