Two Dozen House Republicans propose plan for concealed weapons in school zones

This doesn't go anywhere near far enough, but the notion that people could object to off-duty or retired police from carrying guns in school zones is very difficult for me to understand.  Is there any evidence that police with guns will endanger others?  Seriously?  From The Hill newspaper:

Two dozen House Republicans proposed legislation on Thursday that would allow off-duty and retired police officers to carry concealed weapons in school zones to help protection children from attacks.
Supporters of the Police Officers Protecting Children Act, H.R. 2541, say the bill would give schools the ability to seek this added layer of protection from random acts of violence, like the one that claimed the lives of 20 children last year in Newtown, Conn.
"This common-sense bill addresses a question on all of our minds: how do we keep our children safe?," said Rep. Vicky Hartzler (R-Mo.), the lead sponsor of the bill. "These dedicated men and women of law enforcement should not be barred from providing an extra layer of security for our schools just because they are off the clock or have retired from active service to their communities." . . .