I'll just about guarantee that that 686 is not a former RCMP revolver. The barrel length on that specimen appears to be 4". The minimum barrel length of any handgun for anyone in CANADIA, including RCMP is 4.1". I have several friends that I hunt with that are RCMP and the only revolver I have ever seen any of them carry was a DAO Ruger, Security Six (?), with a 5" barrel. For the last 15 plus years that I have hunted in CANADIA they have been issued 3906's loaded with Winchester Ranger 124 gr +P. Last year they were all pumped at the thought that they MAY be going from the 3906's to the M & P 40 Cal (10 round mags, still it's 4 more than the Security Six and 1 more than the 3906). If it was legally re-imported it will have the importer's name, City and State stamped on it someplace. Check inside the triggerguard with a magnifying glass as I have seen a couple that were stamped there in micro print that sometimes looks like a scratch. Another couple of odd places I have seen the re-import stamp, on one 6" M10 it was on the INSIDE of the frame under the side plate and on a 6" Python it was stamped inside the crane cut out on the frame. All of the looking in the world will do you no good if it was re-imported by S & W, as the original manufacturer is not required to restamp their info on the firearm as it is already stamped on the frame. Hope this helps.
Class III