"Kill La Touche" is a mission objective in Sequence 11 / Memory 02: Rise of the Assassin
Walkthrough[edit]
Getting to La Touche without any preparations can take a little while. You want to circle around to the Southern side of the area. With some careful work you can pick off the local Snipers and thugs. After that, slip behind La Touche carefully and you can get a quick kill on him.
Prisoner Approach - Unique Kill[edit]
Complete the Assassination Opportunity objective for this mission. This will get Arno inside the the prison cell where they are drawing their execution pool. After a short cinematic, Arno will be called forward. Follow along with the Guards. They will take you up to the platform. You will be given a short window to quickly assassinate La Touche. Just go up the stairs, approach and then quickly assassinate him.