A “cop-killing” video game that allows players to act as gangsters trying to gun down officers on the street is generating opposition among city police advocates.

A City Council member of Queens, Eric Gioia, yesterday said he would try to pressure city retailers not to sell the game, “25 to Life.” It hit stores last month.

“This is so far beyond the bounds of decency that it shocks the conscience,” Mr. Gioia told reporters at City Hall. “In this city, we have deep respect and admiration and gratitude for the brave men and women who make us safe every single day. This type of game is not appreciated and this type of game is not wanted in New York City.”

Produced by the British company Eidos and billed as a “cops and robbers” shootout, the game is set in an unspecified urban landscape and lets players choose whether they want to act as law enforcement officials or drug-dealing gang members. If they choose the latter, players can advance by killing police officers.

“25 to Life” follows other games that have drawn criticism from some politicians for using the latest computer graphics technology to create increasingly realistic depictions of violence. Games such as “Grand Theft Auto” and “Counterstrike” allow players to act as gang members and terrorists, respectively.

“I don’t know what these game makers are thinking about,” the president of the Detectives Endowment Association, Michael Palladino, said. “I can think of two words to describe this type of video game: greed and poison. The game makers are driven by greed, and our children are being poisoned.”

Mr. Gioia, a Democrat who is chairman of the Council’s Oversight and Investigations, said “25 to Life” is particularly offensive to New Yorkers, as two city police officers have been killed by guns in recent months. Though the game is rated “M” and cannot be sold to children under 17, Mr. Gioia cited investigations that found it was easy for minors to gain access to “M” rated video games.