Instagram maps sharing accuracy?

It sucks, but my boyfriend and I share locations on IG, and I saw his location late at night at a known “shady” spot about a mile away from his place. It updated half an hour later and showed him at home. He swears he was home the whole time and asleep and it must have been a glitch.

Does anyone know how accurate it actually is? Because my location has never glitched more than a block for me or my friends and this has unfortunately caused some tension between my boyfriend and I.