SELECT all rows when a variable is null How do you select all values when @Troop is NULL. And if there's a better way to do this all together then what would that be?

WHERE DateModified BETWEEN @BeginDate AND @EndDate
    AND  
    d.CreatorLEA = 
        CASE
        WHEN (@Troop IS NOT NULL) THEN @Troop
        ELSE -----SOMETHING HERE?------
        END
If I understand what you are asking then like this.

WHERE DateModified BETWEEN @BeginDate AND @EndDate
AND  (@Troop IS NULL OR d.CreatorLEA = @Troop)