False : one cannot legally prevent a custodial parent from interacting with the administrative staff of any facility while that facility has custody of that person's child.
In the encounter, custody status of the parent is moot considering the facility claimed the parent was trespassing. The police made an initial investigation and decided there and then that the person was, indeed, trespassing. Custody was irrelevant. The police legally must respond to the trespassing as a prima vacie claim.
Attempting to do so is known as kidnapping.
Kidnapping is the unlawful asportation and confinement of a person against his or her will. The victim's arrest was lawful (see below) so a claim of kidnapping is not legally valid.
He was told he was under arrest.
Extremely misleading : he was not at any time under arrest during the actions you describe above.
The moment the police uttered the words "You're under arrest", the action became legally valid. The courts must decide (later) if the arrest was warranted and lawful.
...the statement "you are under arrest" was first uttered while the officer committed several counts of attempted murder by bashing the victims head against a concrete wall.
According to the date and time in the police video, the victim was informed that he was under arrest at 2019 01 11 T18:45:17Z which would be about quarter to 11 in the morning, Eugene local time. At that time, the police and victim were approximately 6 to 8 feet from the concrete wall you mentioned.
Being under arrest, he can legally be subjected to a forcible takedown.
False. This is the crime of battery.
If the arresting officer uses excessive force that could cause “great bodily harm,” the arrestee has the right to defend him. That’s because most states hold that an officer’s use of excessive force amounts to assault or battery, which a victim has a right to defend against. However, during an arrest, a takedown (forcing a person to the ground) does not, in itself, constitute excessive force that could cause great bodily harm.
if under arrest, the weapon cannot legally be utilized in any way.
False : bad elk v. us, for instance.
Most states have, either by statute or by case law, removed the unlawful arrest defense for resisting arrest. The Supreme Court held the arrest in Bad Elk to be unlawful due, in part, to the lack of a valid warrant. Technically and legally, Bad Elk was not under arrest.
... Executing both cops would have been quite legal under the standard and established usage of the concept of necessity defense, unless it was done after they had stopped their criminal behavior.
Again, I would point out that at no time were the police outside the laws of their jurisdiction. There was no criminal behavior on the part of the police.
The cops were blatantly identified as cops,
This is true; it does not, however, have any legal weight.
Not sure how a police officer identifying himself as a police officer would not be a legal declaration. There were multiple indications that the two individuals confronting the victim were, in fact, police officers and, as such, could function as such. Legally.
In the physical struggle, when the victim pulled the weapon, it justified the first as well as the second (lethal) shot by the cop.
False; while this would have been true in a fairly normal case, felony murder can never be legally justified by a necessity defense, nor by any other measure.
Legally, there is basically no way in hell this police officer did not commit a firmly criminal murder.
An after-action analysis and legal review found otherwise.
From the very instant the officer asked the man to leave - the first qualifying felony - that man could have started a mass shooting of the officer, or other students, or anyone else, or done literally anything else, and the officer could not have a legal right to shoot him, literally no matter what.
I'm not sure how that would work. "... the officer asked the man to leave..." qualifies as felony? Mass shooting of other people does not legally allow an officer (or anyone else) to stop it?
Under law, there is literally no series of events which could have justified any action by this officer which resulted in this man's death, legally speaking. Literally none.
Hypothetical, then: You sit in a chair, unarmed, restrained. I walk up with a gun and declare I am going to shoot you. The officer has a gun and can point it at me to stop me. Are you saying that the officer cannot legally shoot me to prevent your death?
Surely you're just baiting me to continue the discussion.