Harry K. Schwartz, 85, of Society Hill, a lawyer who served as a housing official and policy aide in the Carter administration and who later wrote groundbreaking tax law enabling historic preservation, died Sunday, Dec. 1, of congestive heart failure at home.

Mr. Schwartz was a nationally known expert on state tax incentives for the rehabilitation of historic buildings. He participated in the drafting of the Pennsylvania Historic Tax Credit Law and provided advice to other states on tax credits for historic preservation.

In 2006, Mr. Schwartz received the National Trust for Historic Preservation’s Sen. John H. Chafee Award for Outstanding Achievements in Public Policy.

“As a legal expert, he consulted with many states to evaluate, draft, and sign into law progressive historic tax legislation,” said Paul Edmondson, the trust’s president and CEO. "He helped protect the historic places that tell the full American story.”

From 1963 to 1968, Mr. Schwartz served as a legislative assistant to U.S. Sen. Joseph S. Clark. He served as Clark’s aide in helping to secure President Lyndon B. Johnson’s passage of the Civil Rights Act of 1964 and the Voting Rights Act of 1965.

In 1977, Mr. Schwartz was nominated to be an assistant secretary for legislative affairs in the U.S. Department of Housing and Urban Development under President Jimmy Carter. Earlier, Mr. Schwartz had helped direct Carter’s presidential campaign.

In 1979, Mr. Schwartz joined the White House domestic policy staff, with responsibility for solar energy and energy conservation. He helped prepare Carter’s message advocating the development of solar power long before that energy source became mainstream.

A Philadelphia native, Mr. Schwartz graduated from Central High School in 1951, Harvard University in 1955, and the University of Pennsylvania Law School in 1959. He began his career in 1960 as a clerk at the U.S. Court of Appeals for the District of Columbia Circuit.

He served as an assistant U.S. attorney in Washington, and as a lawyer for the U.S. Securities and Exchange Commission in 1962 and 1963. He spent much of his career shuttling between Philadelphia and Washington.

A longtime resident of Society Hill, Mr. Schwartz was active in community affairs. From 1969 through 1976, he served as a member of the board of the Society Hill Civic Association. Later, he served on its committee for historic preservation.

Mr. Schwartz was a partner in three law firms during his career: Dechert Price & Rhoads in Philadelphia; and Lane & Edson and Dewey Ballantine, both in Washington. His specialty was mergers and acquisitions.

After retirement from law practice in the mid-1990s, Mr. Schwartz was appointed director of public policy for the National Trust for Historic Preservation. During that time, he developed and lobbied for a federal historic home ownership tax credit, but it never became law.

He served on the board of the Preservation Alliance of Greater Philadelphia from 2008 to 2017. For his service to the alliance, he received the Rhoda and Permar Richards Award in 2015.

The law that Mr. Schwartz was instrumental in drafting provides state tax incentives for owners of historic income-producing properties — not residences — to preserve and restore their buildings, said alliance executive director Paul Steinke.

“If it didn’t exist, far fewer buildings would have been preserved locally and nationally,” Steinke said.

Mr. Schwartz was engaged in neighborhood opposition to the proposed South Street Expressway, a highway that planners saw as the southern link in a loop including the Schuylkill Expressway (I-76), the Delaware Expressway (I-95), and the Vine Street Expressway (I-676).

The expressway would have forced demolition of homes and businesses on South Street. The plan surfaced in the 1950s and 1960s but was scrapped by planners in 1974 after a study questioned its usefulness.

Mr. Schwartz was president of the Central Philadelphia Reform Democrats and vice chairman of the Southeast Pennsylvania chapter of Americans for Democratic Action.

Mr. Schwartz was often quoted in the press. In 1979, in an article on pedestrian hazards, he told the Los Angeles Times: “In Philadelphia, nobody respects anyone on the streets. It’s a race to the death between drivers and pedestrians. Philadelphia is the jaywalking capital of the world.”

Starting in 2006, he became an occasional contributor to The Inquirer’s op-ed page. In one article, a defense of Carter’s energy policy, he wrote: “If only we had listened to Jimmy Carter.”

He is survived by his wife, Marinda Kelley Schwartz; children Tony and Amanda; and two grandchildren.

A memorial will be held from noon to 3 p.m. at the Athenaeum of Philadelphia, 219 S. 6th St. Burial was private.