BPM - Multiple users in the same lane

Hi,

We have a process with 3 roles which are the Tax Accountant, Supervisor and Tax Manager. We have created 3 lanes in our BPMN. The process is exactly the same for more than 50 countries so we have more than 20 Tax accountants who will execute these tasks.

How can I trace which user has executed which tasks?

Do I need to code somewhere that the tasks for England are going to User A and the tasks for Sweden are going to user B for example? I would prefer that all my user go to the same UWL, that they can take any task but that we can keep a log of who has executed what. Can you please explain me how to do this and if this is the best way to proceed?

Thanks

Martin