General assumptions: You must use all five disguises available in the fifteenth game mission.
The easiest way to obtain court security guard disguise appears in the Courthouse stage. You can attack one of guards in secluded places (e.g. the guard in the office room on the ground floor) or get the ready-to-wear disguise located next to the parking lot at the courthouse's back.
Court usher disguise can be obtained in the Courthouse stage. The best way to do this is to attack the usher in the library on the courthouse floor. Remember that you must kill or stun a man.
Tin Foil Hat Man costume can be obtained only in the Courthouse stage. I recommend completing all actions described in the walkthrough of the 15th game mission in the Courthouse - Get to the holding cells in defendant disguise subchapter (this result in Hawke appearing in the toilet and then you can eliminate him safely to obtain his costume).
Judge disguise can be obtained in the Courthouse stage. It is best to get to judge's private chambers and then force him to come here (by using throwable item or computer terminal).
Hope police officer can be obtained only in the Prison stage. Attack any of cops in the prison (e.g. the one guarding evidence or a single cop encountered at the stage beginning).
General assumptions: You must find three evidences.
First evidence can be obtained in the Courthouse stage. It is located in a security room on the courthouse ground floor. This secret can be easily collected in judge's disguise, so Hitman won't be exposed.
Second evidence can be obtained in the Holding cells stage. It lies on the desk in the last room (the one with locked door leading to the prison).
Third evidence can be obtained in the Prison stage. Stop after reaching the corridor after crossing a gate unlocked with a button in guardroom. The secret is in the cell with a single Hope cop. It would be best to wait until this person turns around and stun/kill him then.
General assumptions: You can't be spotted. In order to complete this challenge in 100% you have to do this in all three stages of the fifteenth mission. You shouldn't have many problems with that. In the Courthouse stage watch out while exploring parking lot and in the Prison stage be careful near the guardroom.
General assumptions: You can't use disguises. In order to complete this challenge in 100% you have to do this in all three stages of the fifteenth mission. Most problems can be encountered in the first stage - Courthouse. I recommend trying to run to the passage leading to the holding cells and setting difficulty level on Normal.
General assumptions: Stop the video playback of the evidence during the trial.
For obvious reasons this challenge can be completed only in the Courthouse stage. You have to reach one of two computer terminals and interact with it. First terminal is located on the balcony on the courthouse floor.
Second terminal is located in the room adjacent to judge's private chambers. In both cases you have to wait until given terminal becomes active.
No Collateral Damage
General assumptions: Complete the mission without casualties. You shouldn't have problems with that, especially that persons wearing disguises you may obtain can be only stunned.
Take the Fall
General assumptions: Take the Tin Foil Hat Man and participate in the trial.
This challenge can be completed in the Courthouse stage. Detailed instructions on how to compete its objective can be found in the Courthouse - Get to the holding cells in defendant disguise subchapter. As a reminder the best way to obtain the disguise is to follow him to the toiled in the trial break (screen above).
Once you put on Hawke's costume, you have to return to the courtroom and wait for the judgment. In this moment the game will count the second part of the challenge as completed.