CHICAGO (CBS) — Aldermen have given preliminary approval to an ordinance that would require constant security for any places licensed to grow or distribute medical marijuana in Chicago.

WBBM Newsradio Political Editor Craig Dellimore reports the City Council Zoning Committee easily approved a measure that would require all medical marijuana dispensaries and cultivation centers to hire around-the-clock security guards.

Ald. Edward Burke (14th), who co-sponsored the proposal, said medical marijuana distributors and growers in other states often have become targets for burglaries, robberies, and worse.

“Certain marijuana businesses in Denver, Colorado, suspect that recently-hired security guards may be discouraging would-be thieves; and many industry advocates have encouraged the hiring of security guards at marijuana stores,” he said.

Security consultant James Smith, a former federal marshal, said in other states where medical or recreational marijuana is legal, the need for security at marijuana growers and dispensaries has been demonstrated.

“Because marijuana remains illegal at the federal level, banks and security firms deny services to many cannabis-related businesses,” he said. “That leaves these businesses cash-based and vulnerable; and a magnet for criminals who like the idea of unguarded counting rooms, and shelves lined with lucrative cannabis plants.”

The measure was sent to the full City Council for consideration at its next meeting on Wednesday.