ALBANY, N.Y. (CBSNewYork/AP) — Mothers and other relatives of a dozen New Yorkers killed by police have brought cardboard coffins to the New York state Capitol Monday, to urge Gov. Andrew Cuomo to appoint a special prosecutor for future cases.

Setting the black cardboard coffins outside Cuomo’s office, the mothers say he promised this year to appoint such a prosecutor by executive order if the Legislature fails to pass his proposal to establish a special monitor to review grand jury investigations of police who kill unarmed civilians.

Gwen Carr is the mother of Eric Garner, who died last year in a police chokehold on Staten Island. A grand jury declined to indict the officer who allegedly administered the chokehold, Daniel Pantaleo.

Carr said prosecutors who work regularly with police aren’t capable of bringing police death cases.

The Legislature is set to adjourn this week.

A Cuomo spokesman said talks with legislators continue.

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