D.C. Mayor Vincent Gray pledged throughout his 2010 mayoral campaign to end years of systematic city underfunding of the District's public charter school students compared to their peers in the city's traditional public school system. Yet, after three budgets, he has failed to deliver on his promise.

The mayor's fiscal 2014 budget underfunds the District's public charter school students by more than $1,700 per student in school operating funds, compared to students enrolled in DC Public Schools.

The mayor also proposes to set funding for school facilities at $3,000 per charter student, but at $9,693 for each DCPS student.

Charters are tuition-free, city-funded public schools that operate independently of DCPS. Free to shape their own academic curriculum and school culture, charters are held accountable for improved student performance by the city's Public Charter School Board.

These public charter schools, which will educate 45 percent of the District's public school children next year, have delivered. D.C.'s charters have an on-time high-school graduation rate 21 percentage points higher than regular DCPS high schools.

And African-American students enrolled in charters score on average 16 percentage points higher in math, and 13 points higher in reading, on D.C.'s standardized tests than their DCPS peers.

Over the past six years alone, the gap in school operating funding has totaled $260 million -- an average of $4.5 million for each current public charter school in operation during those years.

Under D.C. law, school operating expenses are supposed to be funded through a Uniform Per Student Funding Formula to ensure that DCPS and D.C. public charter students who are at the same grade level, or have similar special education needs, are funded equally.

Sadly, this mayor, like his predecessors, has flouted city law by funding DCPS, but not charters, with millions of dollars every year outside the funding formula.

This year, the mayor's budget would provide an additional $80.4 million to DCPS, but not to D.C.'s publicly funded charters. Gray has also continued many other city policies which unfairly penalize charter students.

Charters are funded only for students who actually enroll, whereas DCPS gets city funds based on estimated enrollment that proves to be overly optimistic every year.

DCPS also routinely receives additional funds from the city when it overspends its budget, while charters have no choice but to live within their means.

The mayor also has attempted to keep surplus DCPS school buildings out of the hands of charters, who desperately need to buy or lease adequate school space. Of the 15 schools slated for closure by DCPS Chancellor Kaya Henderson, none is scheduled to be leased to a public charter school.

Gray's attitude toward these precious public resources is unfortunate on many counts.

First, District law states that charters must be offered school buildings no longer being used by DCPS to buy or lease before they can be offered to private developers.

Second, under successive mayoral administrations, the city has allowed school buildings DCPS is unable to fill to rot, or sold them off to private developers for luxury condominiums.

Consequently, many charters are forced to rent and renovate costly former office, warehouse or retail space with expensive commercial loans. Charters' annual facilities allowance often proves insufficient to fund this, forcing them to use funds which should be invested in academics.

Other unfair city funding practices have yet to be addressed by the mayor. How can the administration justify, for example, routinely providing crossing guards at DCPS campuses but almost always failing to do so at charter campuses?

Recently, District public charter school leaders testified before the D.C. Council on how the city's unfair funding undermines their effort to provide students with a quality public education.

Charters disproportionately serve the city's disadvantaged neighborhoods. Will council members take a stand for these students?

Robert Cane is executive director of Friends of Choice in Urban Schools.