Ald. Edward Burke (14th) said he "could not believe" so few people were on the Chicago Police registry of gun offenders. View Full Caption DNAinfo/Kelly Bauer

CITY HALL — An effort to make sure Chicagoans know whether they live on the same block as someone convicted of using a gun to commit a crime foundered Tuesday when aldermen realized very few convicted felons are listed on a 4-year-old city registry.

Ald. Edward Burke (14th) — who authored the 2012 ordinance requiring the Chicago Police Department to keep track of felons convicted of gun crimes — was incredulous that the registry, using state-provided data, lists only 1,942 people. Some 24 percent of those people have not complied with the law by registering, Chicago Police Deputy Chief Kathleen Boehmer said.

"I just can't believe this," said Burke, who led the special joint meeting of the Finance and Public Safety committees Tuesday in an effort to expand the reach of the registry by requiring city officials to mail residents a letter or postcard when a felon or sex offender moves near their home.

Another 2,243 Chicagoans are registered as sex offenders, Boehmer said.

Seething, Burke tabled that effort as he and other aldermen grilled Boehmer about why more gun offenders were not required to register with officials.

"It defies logic to think that there are less than 2,000 convicted gun offenders in the City of Chicago," Burke said. "There is a glitch in the system somewhere."

Only people convicted of using a gun to commit a crime who move to Chicago after being released from jail or prison are required to register with the city, Boehmer told aldermen.

Only 100 people convicted of gun crime have been arrested for failing to register with the city, Boehmer said, pledging to review the registry to make sure it was accurate.

Burke and other aldermen were incensed that state prison officials notify the Police Department that someone who has been convicted of a gun or sex crime moves into their wards via a carbon copy of a paper form. That data is entered into online databases, Boehmer said.

Ald. Matt O'Shea (19th) called that "nonsense."

Aldermen should be notified when someone on a city registry moves into their wards, said O'Shea, who went door-to-door to inform residents that a convicted sex offender attended a church carnival in violation of the terms of his release.

Ald. Raymond Lopez (15th) said the Police Department's online registry is cumbersome and took too long to load Tuesday morning.

"The more information we can get to our residents to help them protect their families is well worth whatever the logistical hurdles we need to overcome," Lopez said.