Nobody can bypass the security on an iPhone but Apple, requiring them to do so isn't requiring a company to assist in a search, it's requiring a company to use its unique position as the manufacturer to damage their product.
Unfortunately, I think this sort of example paints you into a corner. The court is not requiring the company to permenantly damage the product, any more than a locksmith who opens a locked door to assist in the execution of a warrant is damaging the door. Once the court has what it requests it is trivial to reinstall the original firmware.
There is an old saying that hard cases make bad law. This is a hard case. The defendants are both heinous and deceased; they lack standing to resist and few will support such an effort. Apple is a third-party here and is on such shakey legal ground that they are left defending themselves in the court of public opinion because they know they are going to lose in an actual court. Bad things tend to come out of situations like this.
Can you explain how that duty comes to be?
And since you asked, I would bet that most of the people sitting on a jury deciding if you go to jail or not for impeding the execution of the warrant probably think that your duty to act in such a situation is considered a part of the price of admission to civil society.
A safe is a container filled with physical objects: property. Property is subject to search and seizure with appropriate warrants, levies, writs, orders, wants, etc.
A phone is a container filled with information. The only physical property relevant to evidence consists of the electromagnetic state of the memory on the device. This would be no different from the bioelectric state of the neurons in the human brain, which coincidentally, also is a container filled with information. In both cases, there seems to be easy precedent to state that the information in those containers represents protected information, as it pertains to the possibly incriminating testimony of that information.
A safe can be physically removed and brought to a place where there are more specific tools available to access its physical contents. I stipulate to that.
A phone can also be physically removed and brought to a place where ... What? What tools exist to interrogate the electromagnetic state of the phone that aren't already accessible? Asking Apple to create some software allowing them to unlock and read the information is tantamount to asking a neuroscientist to create software allowing them to unlock and read your mind.
Not trolling, these are my sincere beliefs. Are they wrong?