I also just recieved a call saying his name was Brandon Walters and to drop my work and call back immediately - he was with CR Tax Crimes (muffle muffle) and also said if I did not return the call he could only wish me good luck - figured it sounded fishy!
Same call as everyone else, and also got a call from 844-850-3567 a week ago too. Also the robo call does not say lawyer as mentioned by Cathy above, it says Attorney(US terminology). Last weeks call said "Canadian" Revenue Agency, it's Canada Revenue Agency. SCAM. You can check CRA, they don't use Robo calls. Intimidation works on some people and they give these scammers their CC info. Never, Never, do this. You don't give any info to these people. You call CRA direct from the phone number in the phone book(or go to this website if you trust my post here http://www.cra-arc.gc.ca/ or look it up if you don't believe me) and have them look into your account. They'll tell you that there is nothing wrong. Don't let these scammers get to you.
Received a voicemail today from a very suspicious sounding robot that said: "This message is from Canada Revenue Agency... at hand is extremely time sensitive, so the very second you receive this message, I need you to leave your work aside and dial a number to the CRA Tax Crime Division. The number is 647-560-7547, repeat the number is 647-560-7547. This is Officer Brandon Walters and I am working with CRA Tax Crime Division. Now if you fail to return the call or in case if I don't hear from your attorney either, then the only thing which I can do for you is wish you good luck as the situation unfolds on you. Good bye."
FYI, if CRA needs to get a hold of someone, they send a letter first. If they were to call you, a live agent would make the call, not a voice simulator reading such a threatening (and poorly written) script, i.e., "Now if you fail to return the call or in case if I don't hear from your attorney either, then the only thing which I can do for you is wish you good luck as the situation unfolds on you."... Mmmkay, ya. Let me call that number right away before this situation unfolds on me.