ASP.NET postbacks cause Load first

I've been working on an ASP.NET site - pretty much my first serious project with the framework. Many pages do a lot of work in the Load handler to verify that the user should actually be able to see the page, and then fill the page with data. Some of those have buttons on them, which cause postbacks to deliver the notice to the server. This runs the page object setup again, including Init and Load. Therefore, it's not necessary to repeat authentication checks in individual controls' event handlers, since that code won't be reached if Load's code ends the request.