A plot to kill the lieutenant governor for tampering with the prison system sounds crazy, Alabama officials say, but extra bodyguards have been assigned and a full-scale investigation has been under way for a week.

The second target of the death contract is an outspoken state senator who headed a committee that investigated the prison system. The contract was rumored to include other public figures who have been critical of the state's beleaguered prison system.

Alabama prisons are under federal court orders designed to relieve severe overcrowding. Critics charge that the antiquated system allowed inordinate power to a coalition of guards and trusties without adequate supervision.

A spokesman for the Alabama Bureau of Investigation confirmed that the probe centered on a prisoner's claim a week ago that a contract had been put out on the lives of Lt. Gov. Jere Bearsley and state Sen. George McMillan.

The prisoners volunteered to an investigator for McMillan's prison oversight committee that money had already changed hands. "They were supposed to be worried about losing their jobs if Beasley were elected governor and McMillan lieutenant governor," explained an official.

Election is next year. Neither is an announced candidate, but both are campaigning actively.

The same day two prisoners at a prison trade school near Mobile stole a laundry truck and smashed through the chain link enclosure, carrying the gate with them. The others had escaped earlier. One of the four was part of the "Dawson Gang," called by the state attorney general the "kingpins of organized crime in Alabama."

The escape was treated as if it were associated with the alleged death and a round-the-clock guard of state troopers was kept with Beasley all last week. McMillan has refused extra protection.

DeWitt Dawson, his brother, Pride, another brother, Homer Gene, a half-brother and a nephew have variously been convicted of charges ranging from bank robbery to car theft and income tax evasioN.

DeWitt Dawson, called by state police "the mind behind the gang," has often exhibited a certain flair. When IRS agents went to arrest him, they found a note on his door, "I gave at the office." He pleaded guilty, took out an advertisement in the local newspaper denying any real guilt, and state troopers claimed he spent much of his sentence in relative freedom at a federal minimum security facility at Montgomery last year.

But investigators take the death threat seriously, because there have been others in the prison system over the past few years. For example, four years ago, a prisoner said a deputy offered him $500 to drown the prison commissioner, L. B. Sullivan. His story was confirmed by polygraph tests.

The deputy commissioner denied the story, resigned, and moved out of the state.

State investigators declined to comment further last week except to say their investigation is still active. Prison commissioner Judson Locke also declined comment.

Official attitude remains one of cautious increduilty. Most discounted a theory that the threat originated with rival political candidates. Since Gov. George C. Wallace by law cannot succeed himself and has established a campaign organization for a U.S. Senate race, the governor's race is open.

Beasley's extra bodyguards have helped keep him before the public. Another gubernatorial candidate warned facetiously that he would announce that he, too, is a victim of the threat. He joked that the announcement would come late yesterday afternoon to fill the weekend news vaccum.