How do I set column rules to the left side of text columns instead of in between?

Unless I'm misreading both the question and Randy's answer, you can adjust the position of the column rules to either side of the gutter using the Horizontal Position field:

If the OP means putting a column rule on the outside left (left page margin), that can only be done manually, on each page or a parent page. But you don't have to have rules centered in the gutters if you want them offset.

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InDesign's automatic column rules function puts lines between columns of text.

To get the effect you're looking for, you're going to have to add it yourself — either by using ruler guides to set the spot and drawing them in as you want to apply them case by case, or by providing for them globally by using the same process to draw them into parent pages.

Hope this helps,

Randy