Tim Cook has publicly opposed an order to help decrypt a mass shooters phone in an FBI investigation. The court order basically asks Apple to create a special version of iOS which disables security measures, and Rich Mogul suspects that this case is designed to serve as precedent to create backdoors.
On the technical side, Apple has designed its hardware such that it uses an embedded key to prevent stealing data directly from flash memory. So you are forced to use the phone itself unless you are willing to spend probably a few millions to carefully examine the processor itself to read the embedded security fuses, with a fair chance that you permanently destroy your access. So Apple is the most reasonable route to gain access.
The trouble is that this demand is worded in such a way that it can later be extended to encompass more and more cases:
The FBI should get the modified software. This is very problematic because it makes the backdoor widely available, and very cheap once created. Especially there is no incentive for the FBI to properly safeguard this master key to every iPhone on the planet.
Software locked to this iPhone. Sounds great in principle, but this would require an awful lot of engineering to make it impossible to modify.
Apple must provide a backdoor. This could later be extended to force Apple to provide special software for ongoing investigations, or even a general master key for law enforcement.
If you were to ask for this information in a manner that reduces the risk of it being repeated, you would intentionally structure all the steps in such a way to minimize any risks. The software would be created by Apple, and would never be on a networked machine. The cracking would be done on Apples premises, and the FBI would deliver every day a new file with the passcodes to be attempted. Should the right code be found, the code would be noted, and the phone returned with any traces of the special software removed. Also once the cracking starts, all sources and any other copies but the one running on the phone would be destroyed, to reduce the risk of a break-in.