presuming

With infinitive object: to be so presumptuous as (to do something) without proper authority or permission.

“I wouldn't presume to tell him how to do his job.”

To perform, do (something) without authority; to lay claim to without permission.

“Don't make the decision yourself and presume too much.”

To assume or suggest to be true (without proof); to take for granted, to suppose.

“Dr. Livingstone, I presume?”

To be presumptuous; with on, upon, to take advantage (of), to take liberties (with).

Confidently or arrogantly overstepping reasonable bounds.