How do police precincts get people to stand in a line up?

Question

I mean like, are they volunteers, pulled from a pool? Or do the police pay them?

Answer 1

They  pick   up   Suspects  for  questioning  and  some  

     they   pay  to  stand  in.

Answer 2

your DL pics are usuay pulled or mugshots that are on file...

Answer 3

they use actors and look-alike officers

Answer 4

Most of them are cops that they find similar to the accused.

Answer 5

I was in a line up once. The cops waited outside my college and offered people 10 bucks until they had enough "suspects". They took us to the police station, lined us up with the real suspect and then drove everybody home.