The type of tasks that you are, or have been, in charge of will help the hiring manager to understand your level of responsibility and competency. Talk about the biggest project or task that you were ever put in charge of.
"I have been given a lot of great responsibility in my current position. The most important of those tasks is to take over the team lead role when my manager is away. I am expected to step into his shoes and I can say that I do a great job with it as well. I enjoy the responsibility and have proven myself to be a competent leader time and time again."