D.C. MAYOR Muriel E. Bowser (D) has until Feb. 16 to decide what to do about legislation that would establish a lavish paid family leave program for people who work in the nation’s capital. Given that the mayor has made it no secret that she thinks this is a bad bill — an assessment with which we agree — it is unlikely she will sign the measure. What is unclear is whether she will veto the bill or let it go to the Hill without her signature.

Put another way: Will Ms. Bowser stand on principle and try to block legislation she knows is ill-advised and poses enormous risks for the city, or will political considerations prompt her to take the easy way out?

At issue is Bill 21-415, the Universal Paid Leave Amendment Act of 2016, which would increase taxes on D.C. businesses by an estimated $250 million annually to establish what would be the nation’s most generous paid leave program. There is no question about the value of giving working families paid time off to tend to a newborn baby or an ailing parent, but the approach of this bill is irresponsible and likely unsustainable.

Not only would it require the establishment of a vast new city bureaucracy, but most of the benefits would be paid not to D.C. residents and taxpayers, but to Maryland and Virginia residents who work for D.C. businesses. “This is a significant bill proposing benefits more generous than other existing state programs. As a result, it presents multiple risk factors that may impact timeline and cost” was the ominous warning from the city’s chief financial officer. That caution unfortunately was ignored by D.C. Council members in their rush to approve a bill pushed by labor activists. Nor was thought given to the fiscal uncertainty the city faces with Republicans in control of the White House and Congress.

No doubt the council’s 9-to- 4 final vote in favor of the bill factors into the mayor’s deliberations. Five votes would be needed to sustain the veto, and it is unclear if Ms. Bowser would be successful in changing minds or in persuading the two new members of the council — Vincent C. Gray (D-Ward 7) and Trayon White Sr. (D-Ward 8) — to sustain a veto. Those advising Ms. Bowser to let the bill go to the Hill without her signature believe it would make her look politically weak if her veto were overridden.

We disagree. Looking out — and standing up — for the city’s best interests is never weak. Ms. Bowser should make clear with her veto the folly of this bill and challenge members of the council to work with her administration in devising a better alternative.

Put another way: She needs to show some leadership.