Caller claiming to be the IRS collecting taxes I'm supposedly delinquent on. First of all, I get small refunds back each year, and if I owed the IRS a dime, they would first deduct it from any refunds I'm due. The IRS never collect debts with phone calls. They never make threats. They don't need to. You get a certified letter after you've ignored notices that come via regular mail services. And if you still do not respond, they have all of your personal data and will simply garnish your paycheck or place liens on your property.