Do Golems register as magical when targeted by Detect Magic?

Question

The page on Detect Magic states

Outsiders and elementals are not magical in themselves, but if they are summoned, the conjuration spell registers.

while the page on Golems states

Golems are magically created automatons of great power. They stand apart from other constructs in the nature of their animating force—golems are granted their magical life via an elemental spirit, typically that of an earth elemental.

So, with this information in mind, when one of my players targets a suspicious statue with Detect Magic to determine if it is a golem in disguise and it is in fact a Golem in disguise, what information does Detect Magic reveal?

In case it is relevant, the statue is not recently created. It has been in place for a few centuries.

Answer 1

No, they do not

Golems are created using very similar methods of creating magic items, but are not magic items themselves once created. They are creatures, instead, of type construct.

The Craft Construct feat allows a spellcaster to create all manner of permanent constructs in a process much like magic item creation.

There is absolutely no reference in the rules stating that constructs, or golems more specifically, have a magic aura that could be detected. They are magical creatures, just like familiars and other magical beasts, but that doesn't mean they emanate a magical aura, which is what Detect Magic actually cares about. Not even the higher level version of the spell, Arcane Sight, will actually detect creatures as magical, but the magical auras affecting them and magical items they are carrying.

We also have clear exceptions to this, as Animated Objects if created using temporary magical effects (Animate Objects or Permanency) are stated to be susceptible to dispelling and anti-magic, while permanent constructs are not:

Not all constructs are built with the Craft Construct feat. Spells like animate objects allow a caster to temporarily animate an existing object. These constructs are in many ways weaker than manufactured constructs, as they are susceptible to dispelling and antimagic.

A caster can use the animate objects spell to instantly create a temporary construct. A permanency spell cast upon an Animated Object makes the construct permanent; however, it can still be dispelled or suppressed by antimagic. Craft Construct creates permanent animated objects not susceptible to dispelling and antimagic.

However, this doesn't mean that a specific golem cannot be detected if they have a supernatural ability like an aura (like a Cryptguard), or a constant magic effect (like the Graven Guardians). They are also identifiable by Knowledge (Arcana), and there are specific constructs that are made for the purpose of looking like a statue, like the Caryatid Column, Guardian Gargoyles and Cephalophore.

This has been confirmed by James Jacobs (Creative Director) on his Ask me anything thread:

What happens when a PC 'scans' a magical beast with detect magic?

Unless a monster specifically has a special quality that says otherwise (and I'm pretty sure there are none that do), you can't detect ANY monster (including magical beasts, undead, or constructs) with detect magic. Creatures don't have magic auras. Spell effects on them do, though.

Answer 2

Detect magic would reveal nothing about the golem

As written, Detect magic detect magic auras, which amount to two things: ongoing spells and magic items, as per the spell description:

A magical aura lingers after its original source dissipates (in the case of a spell) or is destroyed (in the case of a magic item).

The line you quoted from Detect Magic means that creatures summoned by a spell will radiate a magical aura as a result of an ongoing summoning spell keeping them in this plane, but not due themselves. Following the same reasoning, constructs, unless summoned or otherwise affected by a spell, do not have a magic aura that can be detected.

Note that he magic used in its creation is gone after that process ends, and, once created, golems are self-powered and self-contained and do not depend on any ongoing magic effect to function. This is reinforced by the following text in the Antimagic Field spell:

The spell has no effect on golems and other constructs that are imbued with magic during their creation process and are thereafter self-supporting (unless they have been summoned, in which case they are treated like any other summoned creatures).

If there is no magic that can be nullified, there should be no magic that Detect Magic could detect.