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  • Dustin Waybright thinks this is interesting:

it is not necessarily going to evaluate the expressions in left-to-right order. It could decide, based on cost-related reasons, to start with the second expression, and then if the second expression evaluates to true, to evaluate the first expression as well.

From

Cover of Training Kit (Exam 70-461): Querying Microsoft® SQL Server® 2012

Note

You can't assume that SQL server will evaluate expressions left to right. It makes a determination based on system resources.