The call has gone out all across the land: “Defund the police.” It’s a popular slogan, even if the details are far from clear.

In Minneapolis, the plan is to dismantle much of the existing, bias-plagued department. In Los Angeles, Mayor Eric Garcetti has gone to the bottom line: A planned $150 million spending cut — 8% of the LAPD’s 2020 budget.

From the streets filled with protesters to city halls nationwide, and to the halls of Congress, definitions of “defund” differ. The idea has momentum, with governments responding and revising almost by the moment. However defund ultimately is defined — different ways in different places, no doubt — if the demand leads toward meaningful reform, it will do some good.

When I asked Mayor Lori Lightfoot at a news conference this week what “defunding” means to her, she first mentioned underinvestment in “black and brown Chicago.” Then turning to the narrower question of the Chicago Police Department itself, Lightfoot focused on leveraging the 16-month-old, court-monitored police consent decree.

“Of course the consent decree has the potential, if we do it right, to be utterly reformative,” she said.

The mayor pointed to reform steps already taken. Improved training. New orders that limit when cops can use deadly force. Mandatory body cameras for all patrol officers. The release, within 60 days, of video, audio and initial police reports from police shootings.

The Fraternal Order of Police adds to the degree of difficulty for Lightfoot. “We are aggressively attacking elements of the police contracts that are anathema to reform and progress,” she said.

More specifically, Lightfoot wants to stop requiring a signed complaint affidavit before a disciplinary investigation can start. She wants complainants’ identities to be protected until the officer in question is interrogated. She wants an anonymous complaint to qualify as grounds for an investigation.

Lightfoot raised the ante Thursday, saying she has asked her legal team to draft legislation for the licensing of all Illinois police officers. It’s an appealing new idea — and also could provide a new way to hold cops responsible for their actions, regardless of what the FOP contract says. Stay tuned.

Lightfoot’s description tallies a number of good measures. But comprehensive, measurable improvement ultimately will rely on full implementation of the police consent decree. And the “defund” movement, with its focus on budgets, tends to overlook significant complication: Reform itself costs money.

Compliance with the consent decree alone will cost $20 million this year. Other reform costs will add an additional $5.2 million, according to City Hall. The controversial police and fire training academy — a key tool for reform, though it’s opposed by many in the police reform movement — is slated to cost $95 million more.

The paradox of all this is that any significant defunding of CPD might risk slowing implementation of a consent decree that offers the city’s single best hope for meaningful reform.

Zachary Powell, a professor at California State University San Bernardino who has written comparative studies on the impact of consent decrees, cites the risk of unintended consequences. “Depending on how much money is taken away, I would think it would impede the ability to meet the terms of the consent decree and draw out the process for many more years,” Powell said.

The decree has objectives that line up well with those delineated by proponents of defunding. It seeks to stamp out bias, overly aggressive policing, poor tactics, inadequate training and a lack of accountability. Any defunding program would need to guard against starving CPD of resources needed to make progress toward the decree’s goals.

Is there room for budget cuts in the Chicago Police Department? Almost certainly. The CPD has a budget of roughly $1.8 billion and more than 13,000 sworn officers. The Los Angeles Police Department covers an area twice as large with only about 10,000 sworn officers and also a $1.8 billion budget.

Simply saying budgets could be cut does not begin to say where and how. One common idea — reallocating police funds toward mental health, housing or education — sounds appealing in a time of tight spending in those areas. But in redistributing those funds, there would be little room for error.

This past Memorial Day weekend offered just one example. After 10 people were killed by gunfire and 40 wounded, the most mayhem since Memorial Day 2015, City Council critics knocked new Chicago police Superintendent David Brown for cutting costs at the expense of safety. Lightfoot declared Brown’s first big weekend “a fail.” Imagine the outcry if, after some future murderous weekend, defunding is cited as a cause.

As a slogan, “defunding” has a ring to it. As a course of action for Chicago, it is an idea in search of a plan. It would need to be done carefully. In the name of defunding, Chicago cannot afford to undermine a consent decree designed to cure ills that gave rise to the defund movement in the first place.

David Greising is the president and chief executive officer of the Better Government Association.