After a scathing audit found the Valley Transportation Authority’s paratransit provider may have charged as much as $7 million a year for services it could not document, the transit board voted unanimously Friday to end its 23-year partnership with the nonprofit organization that serves disabled riders.

The audit also criticized VTA for a lack of oversight over Outreach & Escort Inc, which failed to supply data supporting its ridership figures in the first ever audit of its $20 million annual contract.

San Jose Councilman Johnny Khamis, a member of the transit agency’s audit committee who led the push for a closer review of the contract, said Outreach showed a “lack of oversight,” and faulted the agency for sloppy record keeping.

Outreach CEO Katie Heatley defended her nonprofit agency, which recorded numerous trips manually until converting to electronic record keeping earlier this year.

“Many things can be explained by technology,” said Heatley, who did not oppose Friday’s vote.

Outreach, which provides 720,000 trips for disabled riders annually, is one of the most expensive contracts VTA has with an outside vendor.

Despite Friday’s vote, Outreach’s contract will continue for a year under tighter scrutiny until a new provider takes over. No changes for riders are planned.

Outreach and VTA operate 215 white Prius cars and vans on South Bay roads and have become a familiar part of the Silicon Valley landscape over the past two decades. They provide specialized, door-to-door transportation for people with disabilities who are not able to ride buses or light rail independently. Those riders use the service for everything from dialysis appointments to trips to senior centers for lunch and shopping. The fee for a one-way trip for riders is $4, but each trip costs VTA about $25.

Auditors complained they were given inconsistent data. For example, Outreach reported 46,410 personal care attendant and 10,193 companion trips in one recent period. Yet, in a follow-up review in January, Outreach reported 112,441 attendant and 94,384 companion trips.

According to a VTA memo, Heatley indicated that the initial data was a “working copy.”

Auditors said the conflicting figures raise more questions about why there are two sets of reports and concerns about the reporting processes. “It’s highly unusual,” auditor Pat Hagen said.

During Friday’s meeting, former Outreach employee Priscilla Gonzales, alleged she been ordered to pad ridership figures, but did not say who told her to do so. “I didn’t feel that was right,” she said, citing it as the reason she quit in February.

The audit found that Outreach’s “complex and murky invoicing process cannot be easily or reasonably validated” and “could not provide reasonable assurance that VTA was being invoiced for services correctly or that performance or regulatory reports were accurate.”

Many records lacked the pickup and drop-off times necessary to validate trips, prompting auditors to question the authenticity of the trips. There are also indications that trip records were modified soon after VTA requested more data, the audit said.

The history of Outreach and VTA is long and complicated. Outreach was granted the paratransit contract in 1993, three years after the Americans with Disabilities Act was signed into law.

A few years ago, the VTA agreed to keep the terms of the original 1993 contract. But during a routine review of VTA’s overall contracts, Outreach’s billing issues surfaced when auditors did a routine review of VTA contracts. That review prompted the full audit.

While Outreach was the focus of the audit, the VTA also was slammed for not requiring routine competitive bids and failing to insist on independent access to Outreach’s systems to verify critical data.

“The current contract does not provide for adequate management oversight, record-keeping and billing practices, which represents an unnecessary risk to VTA,” said Cindy Chavez, chair of the 12-person VTA board and a Santa Clara County supervisor.

VTA general manager Nuria Fernandez promised more oversight.

“We’ve learned some important lessons,” she said.