Medal of Honor winner Jack Lucas, whose reverses have included the loss of a fortune and a murder plot against him by his second wife, will not be prosecuted on drug charges resulting from the discovery of marijuana plants Aug. 28 in an Elkton, Md., cornfield where he was camping.

Lucas had been scheduled for a preliminary hearing yesterday on charges of unlawful manufacture and possession of controlled dangerous substances.

In a prepared statement, State's Attorney John Scarborough of Cecil County said Lucas' "heroic service to his country" was a factor in the decision to drop the charges.

Scarborough also said Lucas had cooperated with Maryland State Police in their investigation of the marijuana case, and "will be a material witness in further proceedings." Lucas could not be reached for comment yesterday.

The 57-year-old war hero had denied the charges against him, saying he pitched his tent in the cornfield while helping Larry Melvin, the property's tenant, build a patio.

"I don't even smoke cigarettes," Lucas said. "I tried marijuana once after my wife tried to have me killed and it made me silly."

His uninsured mobile home in Bowie was destroyed by fire March 25, Lucas said in an earlier interview, and he has since been camping out or living in a shed on the mobile home site.

The marijuana plants were spotted by the crew of a Natural Resources Police aircraft on routine patrol. Melvin, 31, also was arrested and still faces drug charges.

"Mr. Lucas was just in the wrong place at the wrong time," said Daniel Saunders, a district public defender from Chestertown, Md., who represented Lucas.

"He was at an all-time low in his life," Saunders said yesterday. "A friend called . . . and said, 'Why don't you come see me?' and so he did."

Lucas' arrest was the latest episode in a life marked by very good luck and very bad luck.

In 1945, when he was barely 17, Lucas saved the lives of three fellow marines by diving onto two hand grenades in a trench during the Battle of Iwo Jima. One exploded, and Lucas still has more than 200 bits of metal embedded in his body as a result. He qualifies for disability benefits.

For his deed, Lucas became the youngest winner in this century of the Medal of Honor, the nation's highest and most exclusive military decoration. Only 249 recipients survive.

In the years after the war, Lucas married twice, fathered four sons and a daughter, and built a fortune with a chain of butcher shops. By 1973, he said, Lucas Meat Co. in Prince George's County had five stores and 50 employes, and it grossed $2.5 million that year.

Four years later, however, Lucas began a running battle with the Internal Revenue Service, which contended that Lucas owed $135,000 in back taxes and penalties.

Also, in June 1977, Lucas learned through the Maryland State Police that his second wife and her son-in-law were plotting to kill him; the two pleaded guilty to conspiracy and received probation and suspended sentences after Lucas begged the court to show them mercy. Lucas eventually sold his business and the couple finally separated in 1984.

For the past few years, Lucas has lived off savings and the $200-a-month he receives as a Medal of Honor recipient; his disability benefits have been tied up in the IRS tangle, he said.

Saunders said yesterday that the Veterans Administration has agreed to intervene with the IRS to help Lucas reach a solution to his problems with the agency. He said the Veterans Administration has also promised to provide Lucas a home in a veterans facility in the area.

"He couldn't be happier," Saunders said. "At last, he thinks he may be able to see the light at the end of the tunnel."