BRIDGEVILLE, DEL. -- Former U.S. congressman Thomas F. Johnson, 78, a Democrat who represented Maryland's Eastern Shore from 1959 to 1963 and later served a prison term for conspiracy and conflict of interest, died Feb. 1 at Nanticoke Memorial Hospital in Seaford, Del., after a traffic accident. He lived in Berlin, Md.

A spokesman for the Delaware State Police said Mr. Johnson died as a result of multiple injuries, and that his wife, Agnes, 75, who was a passenger in the car, was in critical condition in the hospital.

The one-car accident occurred near Bridgeville on Delaware Rte. 404 at 5:40 p.m., when the car went off the road, hit a mailbox and culvert and overturned, the spokesman said.

Mr. Johnson and his wife had been involved in a serious accident on U.S. 50 west of Salisbury, Md., in December 1985. At that time, their car hit a utility pole and ran into a ditch, leaving both in critical condition.

Mr. Johnson was defeated for reelection in 1962 by Rogers C.B. Morton (R) after he was indicted during the campaign in a savings and loan association scandal. He was accused of accepting money from the Maryland savings and loan industry to use his influence as a congressman. He was convicted in 1968 of conspiracy and conflict of interest and was paroled after serving 3 1/2 months of a six-month sentence in a federal prison in 1970 and paying a $5,000 fine.

Mr. Johnson was born in Snow Hill, Md. He attended Staunton Military Academy and the University of Virginia. He was Maryland's youngest state's attorney when elected at age 24 and became the youngest state senator when elected in 1938 at age 28. He served until 1951. He was elected to Congress on Nov. 4, 1958.

He was the owner and operator of a 300-acre South Point farm and the father of four children.