Has Apple really complied with similar orders in the past?
It's been stated that Apple has unlocked phones 70 times in the past for the authorities. However, this was a very different proposition for older phones without disk encryption. For older phones with no encryption, Apple already had a software version to bypass the unlock screen (used, for example, in Apple stores to unlock phones when customers had forgotten their passcode). So this past history might be completely irrelevant for the case at hand if it's a difference between writing new security-critical software and using software that already existed. In this case, Apple is not refusing to do something that it has done before; the kind of assistance it provided in the past would not be relevant here.
Furthermore, even if Apple had written custom-cracking software in the past, it might reasonably no longer want to do so due to the security risks of writing, testing, and signing this software listed above.
