Pitiful Aim Mr. Rummel (of Hell in a Handbasket fame) discusses the selection of the M4 over the Shotgun by Chicago PD. I do not agree with many of the assertions that he makes in his article.

There is a lot to be said for the humble scattergun. It is probably the most devastating close combat weapon there is...

I don't believe that there are any wound ballistics to back up this assertion that they are the "most" devastating. Shotguns produce large (or a number of small) low velocity wounds while rifles (such as the M4) produce a single high velocity wounds. The permanent cavity of a shotgun pellet is the diameter of the pellet. The permanent cavity of a single rifle bullet is nearly equal to all of the pellets in a .00 buckshot load. In order for a shotgun to be on par with a rifle you need to get all of the pellets on target.

They are also incredibly intimidating, which has caused more than a few violent criminals over the years to give up without a struggle when they found themselves on the business end of a 12 gauge.

I think that this is simply 'folk wisdom.' It implies that the guys who just quit when faced with a shotgun wouldn't just quit when faced with a rifle or for that matter a handgun. By the same token an number of criminals didn't quit when faced with a shotgun, rifle, or handgun. I don't know that there is a way to quantify a psychological advantage of having a shotgun.

They are extremely effective close up, but have less penetration and range than a rifle.

I will say that reduced range and penetration are not necessarily assets, as demonstrated by North Hollywood. Soft body armor will defeat Buckshot, but not 5.56mm. In terms of penetration (or more importantly, over-penetration) 5.56mm JHP is no more penetrative than 9mm in terms of interior walls.

Shotguns are easy to learn how to use, and to use well. This doesn’t mean that no training at all is necessary, just that it doesn’t take nearly as much time to turn a novice into a safe and effective defensive shotgunner as it does to teach the basics of using a rifle in an urban setting.

I don't understand how this is possible. I would argue that a shotgun is much easier for the user to induce malfunctions (short stroking), much harder to reload, and requires reloading more frequently. Additionally the ergonomics of the longer, weight-forward shotgun will be harder for smaller statured officers than the M4.

Are they going to invest in SWAT training for every single one of their patrol officers? Because that is what it would take to minimize the risk to innocent civilians that using weapons with such high penetration in a city would bring.

SWAT training consists of more than an M4 Operators course. I don't see the training hurdle as being insurmountable. The private sector has been turning out competent riflemen with a few days of training.

Have I mentioned that shotguns are only about 20% of the cost of an assault rifle? They are even cheaper than most handguns! So why advocate a poorly reasoned plan to buy assault rifles when a cheaper, easier, safer, and extremely effective alternative is available?

Shotguns are certainly less expensive, but more prone to breakage than the M4. I will not dispute that shotguns are effective within their operational parameters, but easier and safer I have to disagree with.