If you're lodging and organizing an Australian spouse visa program and the foundation of your eligibility is a de-facto relationship with an Australian partner visa or permanent resident, then you should prepare and submit a statutory declaration as part of your program.
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Listed below are my suggestions for preparing your statutory statement:
1) Compose the statutory statement in a factual and objective way. Avoid lengthy descriptions and abstract statements. The exception to this is where subjective statements are required and applicable. This will only be true in certain sections of your statutory declaration. By way of instance, you may include subjective statements inside the nature of the persons' commitment to each other' section.
2) This might just be the most challenging part of the application to arrange because the writer of this statutory declaration will have to have a fantastic grasp of the English language, especially written English. However, writing the statutory statement is likely less of a daunting task than you imagine.
3) Wherever possible, the statements of fact that are made in the statutory statement ought to be backed up by the evidence that you are submitting. By making such links, you're affirming the truth of your claims.
4) Although this isn't stated as one of the aspects your case officer will need to take account of, I would suggest that you incorporate a brief opening paragraph that talks about the initial development of your connection as well as a further section that clearly details the period of your cohabitation with your spouse.