Final answer:
The evidence provided for why whites cannot be trusted by Indians includes historical instances of violence, such as the murder of the Secotan chief and a colonist, aggressive expansion policies, and the repeated violation of treaties, illustrating a pattern of broken trust and mistreatment.
Step-by-step explanation:
The evidence that whites cannot be trusted by the Indians includes a historical context filled with betrayal, violence, and broken treaties. Relations between the Secotan and Lane's men deteriorated, leading to the murder of their chief, Wingina Pemisapan. This act of violence witnessed by White, through the brutal murder of George Howe, was an early indication of broken trust between the two groups.
Furthermore, Washington's administration implicitly positioned Native Americans as obstacles to White settlement, leading to continued conflict and the dispossession of Native lands, notably in incidents such as the Shawnee and Miami defending their territory against encroaching White settlers and the infamous suggestion by Field Marshal Jeffrey Amherst to use smallpox-infected blankets as a weapon against Native peoples.
Additionally, the federal government's poor enforcement of treaties that guaranteed Native American lands spelled further distrust. The persistence of emigration and expansion policies, despite numerous treaties, resulted in repeated violations and increased hostility between Native Americans and White settlers.