valid proof when crime scene not under control of accused

[ANRA]

Jurisdiction

Other

country A accuses country B of committing crime in country A. Any evidence produced by A can be suspected of being fake as B does not have any control on the crime scene. How is this situation handled from law perspective?

 

[army judge]

How is this situation handled from law perspective?

Country A declares war against Country B.
Country A sends 2,000,000 crack troops to invade and conquer country B, after carpet bombing and barrel bombing B relentlessly for 30 days before the ground invasion.