While the Legislature did not explain why it drew a distinction between a police and peace officer and a citizen, there is one explanation to be found in part in the statute itself.
The officer need not be correct in his/her reasonable belief that the person the officer is seeking to arrest committed an enumerated felony; nor is the officer restricted to using the deadly physical force to effect the arrest of a person who is in immediate flight from the commission of the felony.
Before using deadly physical force, the citizen must be correct in his/her reasonable belief that the person he/she is seeking to arrest committed an enumerated felony and that such person is in immediate flight from the commission of the enumerated felony.
Given that the police and peace officer is specially trained, inter alia, in the responsible use of firearms under trying circumstances, and that he/she was being authorized to use that deadly physical force on a much broader scale than the citizen, the Legislature wanted some statutory incentive for the police to act responsibly in the use of their broad power to use deadly physical force by holding them responsible for reckless conduct.
In fact, those who opposed the legislation did so on the grounds that the legislation accorded too much authority to the police to use force. (See, 1968 Bill Jacket, Senate Bill S 4104-A.)
For the citizen who could not be presumed to have had training in the use of deadly physical force, and who would be acting often under stress, on the spur of the moment, in response to the commission of an enumerated felony and while the felon was in immediate flight from that felony, and who would often otherwise be a responsible member of the community, the Legislature chose not to hold that citizen accountable for an otherwise justifiable use of force that resulted in injury or death to the wrong person.
Reasonable people may disagree with that decision, but the Legislature made its choice among the options presented and whether we agree or disagree with the law across the board or in its application to a particular situation, we are bound to accept the legislative direction