John S,
Am I mistaken or are not these men wearing the gear of a messenger, Motorcycle Riding Gear ?
I believe that those riders wore their Pistols on the left with the butts forward a holdover of the horse rider messengers of the calvary.
This is what seems to appear in the picture.
I think that what we see is three messengers awaiting orders to deliver.
If that is the case, the Lanyards were a necessary part of the uniform to keep from having the sidearm bounce out of an inadvertently opened holster.
ViggoG
PS: <img border="0" alt="[oops]" title="" src="graemlins/oops.gif" /> One other possibility comes to mind, That these may be "Convoy Out Riders" who ride ahead and direct traffic at intersections. (The Whistles may be the clue.)
ViggoG
see below
OK it seems that you got me again. <img border="0" alt="[ouch]" title="" src="graemlins/c.gif" /> <img border="0" alt="[ouch]" title="" src="graemlins/c.gif" />