Rep. Andrew Jacobs Jr. (D-Ind.) feeds a piece of cheese to his Great Dane, C-5 — named after a transport plane — in March 1975. The social liberal and fiscal hawk died Dec. 28 at age 81. (Joe Heiberger/The Washington Post)

Andrew Jacobs Jr., an Indiana Democrat who served under seven presidents during his 30 years in the House of Representatives, who was known as both a social liberal and a fiscal hawk and who was once described by consumer advocate Ralph Nader as “the conscience of the House,” died Dec. 28 at his home in Indianapolis. He was 81.

Gary Taylor, a family friend and former campaign manager, told the Associated Press that Mr. Jacobs had been in declining health in recent years but did not cite a specific cause of death. He was treated for cancer several years ago.

Mr. Jacobs was a longtime member of the House Ways and Means Committee, which he sometimes called the Mean Ways Committee because he thought it often passed bills hurtful to those on society’s margins. His legislative battles included advocating for public financing for elections, a balanced federal budget, voting rights and civil rights, closing tax breaks and loopholes, and opposing wars that he believed couldn’t be won, explained or afforded.

Mr. Jacobs, whose election to Congress in 1964 was aided by the tail wind of Lyndon B. Johnson’s overwhelming defeat of Barry Goldwater in the presidential contest, was an early opponent of the Vietnam War. He consistently opposed every U.S. war thereafter, which he described as “unconstitutional pseudo-macho presidential wars” in his 1999 book, “The 1600 Killers: A Wake-Up Call for Congress.”

He also wrote in the book that he coined the phrases “war wimps” and “chicken hawks” in the 1960s to describe those who were “all too willing to send others [to war] but never [got] around to going themselves.”

With strong pacifist leanings, Mr. Jacobs was one of about 40 House members and a half-dozen senators who supported legislation to allow citizens to opt out of federal taxes earmarked for the military. The Religious Freedom Peace Tax Fund Act never made it out of committee.

In domestic legislation, Mr. Jacobs, who served in a district representing parts of Indianapolis, called himself a “parsimonious progressive” who sometimes skewered both sides of the political spectrum.

“If you want to know about waste in the Department of Health and Human Services, best not to ask a Liberal,” he wrote in “The 1600 Killers.” “If you want to know about waste at the Pentagon, don’t waste time with a Conservative.”

In favoring what he saw as fiscal accountability, Mr. Jacobs was sometimes derided by critics as a penny-pincher. He believed he was the opposite: a billions-pincher. Backing him, the National Taxpayers Union said the congressman’s persistent voting record against governmental waste, fraud and corruption “has saved the country billions of dollars.”

Andrew Jacobs Jr., whose father was a judge and one-term member of the House of Representatives, was born Feb. 24, 1932, in Indianapolis. After high school, he joined the Marines and was dispatched to the Korean War, where he suffered combat wounds. He graduated from Indiana University in 1955 and its law school in 1958.

He was a sheriff’s deputy and a lawyer before entering the Indiana state legislature in 1959. He failed in his first campaign for Congress in 1962 but was successful in 1964. He lost his seat in 1972 but came back to win two years later and served until retiring in 1997.

Mr. Jacobs’s parsimony was directed as much to himself as to others. He accepted no speaking fees, took no junkets, refused House stamping privileges, took no PAC money, told potential donors not to send checks and, to save electricity and get some exercise, rarely used elevators to reach his upper-floor office in the Rayburn House Office Building.

He refused to accept his veterans disability check and routinely turned down his congressional pay raises. When the House media center provided him with a color television for his office, Mr. Jacobs declined.

“I know of no good reason for viewing [House Speaker] Tip O’Neill in living color,” he quipped.

One of Mr. Jacobs’s few indulgences was adopting a Great Dane as a puppy in 1969. He named it C-5 in honor of one of the Pentagon’s heralded transport planes and whose cost, like the dog, grew and grew and grew. C-5, the Great Dane, eventually reached the size of a Jersey heifer.

For many in the media, Mr. Jacobs was a dream interview. Quick-witted, adept at rhetorical bank shots that caromed around between irony, humor, metaphors and anecdotes, he treated reporters as equals to be embraced, not foes to be duped.

In 1970, the 6-foot-3 Mr. Jacobs became a vegetarian, choosing what he called a “cruelty-free diet.”

“The leanest steak has fat and grease,” he said in a 1977 Vegetarian Times interview.

“You’re putting grease in your body that you wouldn’t pour down your kitchen sink.”

His marriages to Kay Welsh and Martha Keys, a former Democratic congresswoman from Kansas, ended in divorce.

Survivors include his wife of 25 years, television reporter and documentary filmmaker Kim Hood Jacobs of Indianapolis; two sons from his third marriage; and two sisters.

After his congressional career, Mr. Jacobs taught and wrote. He published three books, including “Slander and Sweet Judgment,” a 2000 memoir of his years in Congress.

Though often labeled a cheapskate, Mr. Jacobs credited his frugality with saving his life. Returning to Washington from Indianapolis in 1974, he was told at the airport that the flight was booked except for a seat in first class. It would cost $20 more than coach.

No thanks, he said, even though it was a government-paid ticket.

He booked the next available flight, in coach. The plane he would have been on crashed in a snowstorm as it approached Dulles Airport. All 92 passengers aboard were killed, including one of Mr. Jacobs’s staff members. He saved the U.S. Treasury $20, and the Treasury saved him.