Mass Effect Legendary Edition

It is actually possible to miss this achievement, so you need to be careful here. Your actions in this mission will also affect how ME3 plays out, so make sure you make the right choices here. I had to play through Tali's loyalty mission a second time to avoid getting her exiled as well as keeping her loyalty. I did not have enough Paragon/Renegade points and I also missed talking with the Admirals after the first trial. You need to talk with the Admirals after the first trial (choose "Admirals infighting"). If you do not have enough Paragon/Renegade points, you also need to have chosen the option to hand Veetor to Tali instead of Cerberus, as well as tell Kal'Reegar to stand down (or not and still have him survive) in previous missions in the game. If you do both of these you will be able to talk to them after the first trial, ask for their help, and then you be given an alternative option to [Rally the crowd] at the ending trial. Doing so will prevent Tali from being exiled, as well as keeping her loyalty.

If you hand in the evidence from her father this achievement will not unlock and Tali will not be loyal. If you don't rally the crowd but do not hand in the evidence, Tali will still be loyal and the achievement will still unlock but she will be exiled and will affect ME3.