Despite an unprecedented push from federal prosecutors for harsher prison terms, three former Houston policemen were sentenced today to one year in jail for civil rights violations in the death of a young Mexican American. i

U.S. District Court Judge Ross N. Sterling, acting under an appeals court order overturning his original sentence of probation, again ignored prosecutors' reguests for "a substantial period of incarceration" and instead imposed one of the lightest possible sentences for the felony conviction.

Sterling made no comment at the sentencing, which ended two years of Justice Department and Mexican-American community pressures for more severe punishment for the ex-policemen, who were convicted on charges in the death of 23-year-old Joe Campos Torres in 1977.

Torres drowned after being hauled to a vacant lot, beaten and allegedly thrown into a bayou with the words, "Let's see if the wetback can swim." The case became a national symbol of police brutality against Hispanics in the Southwest.

Mexican-American leaders today rebuked Sterling again, saying he is insensitive to minorities and, as Ruben Bonilla, president of the League of United Latin American Citizens, put it, "may not be fit to continue sitting as a judge."

Nevertheless, the judge's action was the criminal justice system's final judgment on the severity of the crime. Satisfied with today's events, attorneys for the three ex-policemen -- Terry Denson, 27; Stephen Orlando, 22, and Joseph J. Janish, 22 -- said they do not plan to appeal the convictions.

The only thing left is for the three to report for imprisonment.

"We've been through two juries and two judges," said Michael Ramsey, the attorney for Orlando. "The case is over with. The Joe Campos Torres case is over with today."

In October 1977, a state county jury convicted the three men of criminally negligent homicide in the case. The jury sentenced them to one year in prison but suspended the sentence.

Viewing the sentence as unduly light, the Justice Department prosecuted the three men on civil rights charges. That reflected a new Carter administration civil rights policy reversing a 20-year-old Justice Department policy of not reprosecuting in federal courts cases that already had been handled in state courts.

The three could have been sentenced to life in prison on a conviction of violation of Torres' civil rights, resulting in his death, but on March 28, 1978, Sterling sentenced the men to a 10-year suspended sentence, with five years' probation.

On a second, misdemeanor count, he sentenced each to one year in prison. They have remained free pending appeals.

But the Justice Department made an unprecedented appeal of the probation sentence on the felony count, arguing that some jail time must be imposed on a conviction that can carry a life sentence.

The full 5th, U.S. Circuit Court of Appeals agreed, and ordered the resentencing that occurred today.

Lawyers for the three men again spoke in their behalf. Denson is now a carpenter, Orlando an electrician trainee and Janish a fast-food restaurant manager.

The three have stayed out of trouble and have maintained stable family lives, their lawyers said.

Then prosecutor Brian McDonald spoke: "I have the responsibility of speaking for Joe Campos Torres. He has been forgotten by his absence. Joe Campos Torres is dead, and these defendants are responsible [through] a willful and malicious abuse of authority."

He asked for substantial prison terms.

Sterling then imposed the sentences of one year and one day on the charge that the men violated Torres' rights, resulting in his death. But the judge ordered the time to be served concurrently with the one-year sentence on the misdemeanor count. The three are expected to serve less than a year in prison, perhaps nine months, with time off for good behavior.