There are 3 factors:

1) Steffies pretended like a retard and he claimed he has disability, no family contacts, it would be a trouble if he is being discriminated by police, then they had no choice and they decided to liberate steffies.

2) as m0nde said, steffies was crying like a baby and threatened them to kill himself until he is liberated.

3) Steffies offered sucking dicks of policemen and free weeds in order to be liberated.