For purposes of this law, it is. The Government agreed “that Van Buren ‘access[ed] a computer with authorization HK’ when he used his patrol-car computer and valid credentials to log into the law enforcement database” [1].
“The dispute is whether Van Buren was ‘entitled so to obtain’ the record.” The Court found that Van Buren was entitled so to obtain the record, in that entitlement is the operative word. If the file is electronically accessible to the user, they have entitlement to so, *i.e. electronically, obtain it. They aren’t properly authorised or permitted or something else to it. But those weren’t the words used. "Authorized," unadorned, and "entitled so to."
[1] https://www.supreme court.gov/opinions/20pdf/19-783_k53l.pdf
Did he steal your key? Or did you give it to him? If he stole your key, he wasn't entitled to your house. But if you gave him the key, he had entitlement to it.
If this were a friend, not a kid, you might be able to sue her for throwing a party in your house without permission. You would not be able to get her charged with breaking and entering because she overstepped the conditions that came with your key.
Presume they had intent to water and steal at a felony level when they entered.
If they had to break open the door, entering would be burglary.
Using a key they were supposed to have, to enter a building they were supposed to be able to enter? I would say it should be treated like the former case, not the latter case.
US law may not always agree with me, and apparently there are states where shoplifting can count as burglary. But I say stretching the definition that far is ridiculous.
Say I give a neighborhood kid a key to come water my plants while I'm out of town. If they use that key to gain access and throw a party they're trespassing. I don't see why it should be different for a CPU