BART directors stepped back Thursday from a plan to expand a nascent program to nab fare cheats after concerns were raised about its effectiveness and fairness.

The directors made no attempt to end the enforcement effort, but postponed a decision to hire two additional fare enforcement officers until the fall, when they plan to review data from the proof-of-payment program six months after it began.

“I don’t think it makes sense to hire more people into this program until we know if it is effective,” said director Rebecca Saltzman.

The program began in March, when BART unleashed a team of six fare inspectors, non-sworn and unarmed officers, to tackle an epidemic of fare evasion, which officials believe costs the agency $25 million a year or more. The inspectors possess the limited authority to ask riders inside paid areas of BART’s stations or on trains to show Clipper cards or tickets proving they had legally entered the system — and to give them $75 tickets if they can’t or won’t.

A Chronicle report last week raised questions about the efficacy of the $800,000-a-year proof-of-payment program, which issued 1,300 tickets in its first two months but collected on only about 100. BART Police Chief Carlos Rojas has since updated statistics for the first three months to show that the fare enforcement team has issued more than 1,600 citations and received about $10,000 in fines, which amounts to about 133 paid tickets.

Rojas told directors Thursday the proof-of-payment program is not about raising revenue but about changing the culture of fare cheating by convincing scofflaws it’s neither acceptable nor easy to avoid paying fares.

“Anytime you’re looking at a program to change behavior, it is not a profit-making enterprise,” he said, adding that over time, proof-of-payment citations should decline if enforcement is working.

But Saltzman proposed postponing the expansion of the enforcement team until the board can receive analyses of data that show whether the program is cost-effective or whether more money should be spent on other fare enforcement efforts.

The proof-of-payment strategy is part of a multifaceted approach to stop ticket scofflaws that also includes physical changes such as raising walls around paid areas, closing, controlling or placing alarms on swing gates and using technology, including cameras that can count cheats.

Director Lateefah Simon, along with several BART riders at Thursday’s meeting, wondered whether poor or nonwhite people are disproportionately being hit with citations.

The fare officers wear body-worn cameras, which record inspection efforts, and the footage is randomly and occasionally reviewed by BART’s independent police auditor’s office, which also investigates citizen complaints.

Russell Bloom, the police auditor, said a review of 24 videos found no concerns about discriminatory enforcement. BART’s policy, adopted by the board, calls for inspectors to go from person to person, neither skipping nor singling out anyone.

But Simon said an analysis of citations would be needed to show whether disparate enforcement is taking place. Several speakers said some riders are intimidated by the presence of police or enforcement officers, believe they discriminate, and opposed the expansion of the proof-of-payment efforts.

The proof-of-payment program “costs way more than you’re getting back,” said Keziah Plattner of San Francisco. “Our money would be better spent on higher barriers and fare gates.”

Director Debora Allen agreed, insisting that BART should step up its efforts to “harden” its stations against fare cheats. She was particularly interested in raising BART’s waist-high fare gates, which many fare evaders can vault or push their way through.

Tamar Allen, BART’s chief mechanical officer, said workers are focused on doing some of that at the downtown San Francisco stations and others where fare evasion is common. They’re mostly raising walls and working to bring elevators inside paid areas of stations.

A crew of engineers is looking for ways to build higher fare gates, she said, but the effort is probably at least a couple of years away. Allen suggested BART speed the process by spending more money, including on fare inspections.

BART’s fare inspectors examined the tickets or Clipper cards of 10,745 patrons from March to May and issued 1,633 citations. Allen said that shows that about 15 percent of riders are fare cheats, a number well in excess of $25 million.

“This is definitely a revenue impact to the system,” she said.

The budget, which the board approved without the fare inspector positions, calls for $1 million to determine how fare gates can be replaced or retrofitted as well as $1.2 million for other physical improvements to stations to fight fare evasion.

General Manager Grace Crunican cautioned the board to temper its expectations of impenetrable fare gates arriving soon. Replacing BART’s fare gates would be complicated, she said, and engineers aren’t likely to produce more than a look at possibilities anytime soon.

“Your frustration is going to be very high with fare gates,” she said, “because our frustration is very high with fare gates.”

Director Joel Keller urged his associates to support a balanced attack on fare evasion, including physical improvements as well as fare inspectors.

“The notion that you can harden your way out of this problem is not realistic,” he said. “The notion that you can fare-enforce your way out of this problem is not realistic. You need both.”

The decision to postpone hiring two additional officers came as the board approved the transit system’s $2.3 billion budget for the fiscal year that starts July 1. The budget focuses on quality-of-life issues ranging from injection drug users and homeless encampments to dirty trains and stations that are believed to be driving a drop in BART ridership.

In addition to fare evasion efforts, BART devotes $1.6 million to elevator attendants in downtown San Francisco stations, a homeless services outreach team, a restroom program outside stations, and security measures to keep encampments out of stations.

Michael Cabanatuan is a San Francisco Chronicle staff writer. Email: mcabanatuan@sfchronicle.com Twitter: @ctuan