During a home inspection, the deck is evaluated in terms of safety, rather than code compliance, since the home inspection is not a code inspection.
If connections are poor, railings too low, or supports undersized, they are identified as safety issues. In addition to safety, a home inspection would report on wood rot and deterioration.
It is important to keep in mind that there may be regulations requiring a building permit and/or a code to which the deck must adhere.
There are many aspects of a deck that should be considered when discussing the structure. These include: joists, beams, post size, supports, spacing, decking thickness, guard/railing height, and spindle spacing.
All of these elements work together and are especially important when a deck is high off the ground or supporting large loads.