Is it possible for an ankle monitor to mess up on the GPS??

Question

This is a question for a friend of mine who is having trouble with the law and has been placed under house arrest. But now he is being accused of going out of bound when he has not. So he wants me to see if it is possible it is wrong.

Answer 1

They don't drift very far, but I has seen a few of my gps devices do this too. (max like 10-15 metres)

Answer 2

https://www.gps.gov/systems/gps/performance/accuracy/
Though they say Selective Accuracy is no longer used, I still 'recently' watched a GPS device I own [sitting on my floor several stories off the ground] wander me across the street and play in a grassy spot... repeatedly (it did this other places in the city too, I think)
I don't know why that device drifts, but in this one consumer case, they do.