If I equip (and for the sake of argument am attuned, if necessary) a magical staff (e.g. Staff of Defense) and choose to use this as a quarterstaff to attack, does it overcome resistance to nonmagical bludgeoning?

I ask because some staffs say you can use them as a magical quarterstaff (Staff of Power) but most that specify this also include a bonus to attacks made with it. Crawford and Mearls have both stated that you can use an arcane focus staff as a quarterstaff, so I'm not here to argue that. I am just wondering if I start whacking people with my Staff of Flowers if it bypasses resistance. 

Any attack made with any magic item counts as a magical attack. The rules are quite broad.

Quote from SagaTympana >>

Any attack made with any magic item counts as a magical attack. The rules are quite broad.

 Just to double check... does that mean someone with Tavern Brawler could pick up, say... a magic boot and beat the crap out of someone with resistance to non-magical weapons?

Quote from TransmorpherDDS >>

Quote from SagaTympana >>

Any attack made with any magic item counts as a magical attack. The rules are quite broad.

 Just to double check... does that mean someone with Tavern Brawler could pick up, say... a magic boot and beat the crap out of someone with resistance to non-magical weapons?

 If want to call 1d4+STR mod “beating the crap out of someone,” then sure. That’s an attack delivered by a magic item, which fully meets the RAW requirement for a magical attack.

RAW any staff is also effectively a quarterstaff, and even a staff of birdcalls counts as a magic weapon, but I think as a DM I might draw the line at stuff like magic boots of striding and springing, gloves of missile snaring, or a hat of disguise counting as “magic” attacks or else the Unarmed Fighting Style pro’ly just got a whole lot better than it was ever intended to be.

Quote from ArntItheBest >>

I ask because some staffs say you can use them as a magical quarterstaff (Staff of Power) but most that specify this also include a bonus to attacks made with it. Crawford and Mearls have both stated that you can use an arcane focus staff as a quarterstaff, so I'm not here to argue that.

The DMG says this about magic staffs;

Unless a staff’s description says otherwise, a staff can be used as a quarterstaff.

And the SAC says this about magic weapons:

A magic weapon gives you a bonus to attack rolls and damage rolls only if its description says it does. Every magic weapon can bypass resistances and immunities to damage from nonmagical attacks, but only certain magic weapons are more accurate and damaging than their nonmagical counterparts. For example, a +1 longsword and a giant slayer both give you a +1 bonus to attack rolls and damage rolls, whereas neither a flame tongue nor a frost brand provides such a bonus. All four weapons, however, can bypass an earth elemental’s resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks.

So to summarize; all magic staffs are weapons and all magic weapons overcome resistance/immunity. So yes, bring out your Staff of Flowers and go wild.  =D

But does a boot being wielded in a hand count as a magic weapon?

Quote from Farling >>

But does a boot being wielded in a hand count as a magic weapon?

 Doesn't matter. It's still a magic item, which is what matters. The Sage Advice describes a special case but doesn't limit the general rule to that special case. To Sposta's related point, however, I think it's an easy call to make that just because you wrap your hand in a magic glove doesn't mean you're attacking with the glove. It's still your hand that's doing the attack, and your hand isn't magical unless you're a 6th-level monk. That said, common magic items are just as easy, if not easier, to acquire as magic gloves and boots, so I really don't think it's a significant balance concern.

Quote from Farling >>

But does a boot being wielded in a hand count as a magic weapon?

The rules for improvised weapons are known to not exist in their intended state, due to copious tweets by JC.  The nuances of your question interact directly with the absent rules for improvised weapons.  Ask your DM, but here are the related questions by which we know the rules are missing:

1. When you make a melee attack with a longbow, can you apply both the Sharpshooter and Great Weapon Master feats?  RAW, the longbow is a heavy ranged weapon and so a melee attack with it qualifies for both.  We know from a JC tweet that his intent was that improvised weapons lose their qualities, so a longbow (or any other weapon) wielded in an improvised fashion is intended to lose heavy.  Because we have never received the actual rules text explaining this and we have no JC tweets clarifying the RAI, we have no idea whatsoever what the RAI is on a magic item being used as an improvised weapon retaining its "magic" property or not (note that magic is not a weapon property).
   • FYI, because the rules are missing, RAW you can stack the feats.  I've never even heard of a DM allowing this.
2. You can apply the Dueling fighting style when wielding a one-handed weapon along with a shield.  When you do so, will the Dueling fighting style apply to the shield's damage when used to shield bash as an improvised weapon?  Granted, we don't know for certain, but the RAI appears to be (based on the linked rules and, I believe, at least one JC tweet) that an improvised weapon is only a weapon during the attack and not at any other time, while non-improvised weapons are always weapons.  There is no RAW stating this.
3. The rules contradict themselves in terms of how you assign an ability score to a weapon attack roll.  This contradiction is relevant to your question.  I will cover the issues below.
   1. Here is the PHB rule stating you assign the ability score based on the weapon's category of melee or ranged, not the attack's category.  Under this rule, it is impossible to assign an ability score to improvised weapon attacks when made with a non-weapon such as a boot, as they are neither ranged weapons nor melee weapons.
   2. Here is the PHB rule stating you assign the ability score based on the attack's category of melee weapon attack or ranged weapon attack.  Note that "melee weapon attack" and "ranged weapon attack" are never defined in the PHB and have multiple valid definitions under English grammar rules.
      • Here is the rule clarifying that a melee weapon attack means an attack which is both a weapon attack and a melee attack, just as a ranged weapon attack is an attack which is both ranged and weapon.  This means the 3.2 contradicts 3.1.
4. I'm going to tag some improvised weapons to clarify that anyone telling you they have full knowledge of how the RAW works for improvised weapons is lying to you, because the RAW does not exist and fundamentally relies on DM rulings to make them function on the table:
   1. Torch: "it deals 1 fire damage" is deeply problematic.  The issues are:
      1. As the 1 fire damage isn't listed as the improvised weapon's weapon damage, no one knows if the 1 fire damage is an example of specific beating general, meaning the 1 fire damage overrides the general rule that you always apply an ability modifier to weapon damage.  Does a lit torch deal 1 fire or 1+ability modifier fire?
      2. Similarly, an unlit torch presumably deals 1d4 bludgeoning damage (like improvised weapons in general do and clubs do in specific), but we have no rules text clarifying if "deals 1 fire damage" is intended to replace or supplement the base 1d4 bludgeoning.
      3. The "tightest" possible RAW interpretation here is that the 1 fire replaces the bludgeoning, despite how counter-intuitive it is that lighting the torch makes it substantially less harmful, but you apply your ability modifier, as the 1 fire or 1d4 bludgeoning is the weapon's damage.  But this is absolutely not crystal clear from the RAW we have.
   2. Acid (vial) and Holy Water (flask): Both of these have a similar issue to the torch, where the target "takes" the listed damage, which isn't listed as weapon damage for the weapon.  Do they deal 2d6 damage or 2d6 + ability modifier or 2d6 acid/radiant + 1d4 bludgeoning + ability modifier?  Utterly DM-dependent, but as with the torch, the "tightest" possible ruling is that they deal 2d6 + ability modifier, with the acid/radiant damage replacing the bludgeoning damage for the improvised weapon.

So, the best we can guess (while reminding you you should ask your DM), the magic boot will count as an improvised magic weapon (which is neither a melee weapon nor a ranged weapon and has no weapon properties) when you bludgeon someone with it.  It will use your Strength score for the attack and damage rolls and deal approximately 1d4 bludgeoning (although it might only deal 1 bludgeoning). 

I would say that a magic staff can be used as a magic quarterstaff... at least once.

If you hit a heavily armoured figure with a long stick, at some point the stick will break. Quarterstaves are thick, made of hardwood, sometimes shod with iron. They are weapons. Magic staves might not be.

Quote from Greenstone_Walker >>

I would say that a magic staff can be used as a magic quarterstaff... at least once.

If you hit a heavily armoured figure with a long stick, at some point the stick will break. Quarterstaves are thick, made of hardwood, sometimes shod with iron. They are weapons. Magic staves might not be.

 

 Well, there's this from the DMG to take into account.
"Most magic items are objects of extraordinary craftsmanship. Thanks to a combination of careful crafting and magical reinforcement, a magic item is at least as durable as a nonmagical item of its kind. Most magic items, other than potions and scrolls, have resistance to all damage. Artifacts are practically indestructible, requiring extraordinary measures to destroy."

Since there's nothing in the rules about magic staves breaking if you hit things with them, it's probably fine.

Quote from Greenstone_Walker >>

I would say that a magic staff can be used as a magic quarterstaff... at least once.

If you hit a heavily armoured figure with a long stick, at some point the stick will break. Quarterstaves are thick, made of hardwood, sometimes shod with iron. They are weapons. Magic staves might not be.

Sorry but no, just no. As long as the item description doesn't specifically say that it isn't suitable for fighting then all magic staffs are by rules at least as durable as a regular Quarterstaff.

If you have a specific item that you as DM have a specific reason for being especially breakable then by all means go ahead. But as a general rule no

Quote from Lostwhilefishing >>

Since there's nothing in the rules about magic staves breaking if you hit things with them, it's probably fine.

 That's a fair point, however I'm a bit dubious that hitting foes with this

isn't going to break off that curly bit at the top, or that breaking off that curly bit won't affect the magic of the item.

But you are right, allowing someone to hit an enemy with their staff of charming isn't going to break the game.

I am more dubious about wands. Some of them have all sorts of small, intricate bits of decoration. I do rule that some of those are fragile and using them as a club has consequences.

Quote from Greenstone_Walker>>

Quote from Lostwhilefishing>>

Since there's nothing in the rules about magic staves breaking if you hit things with them, it's probably fine.

 That's a fair point, however I'm a bit dubious that hitting foes with this

isn't going to break off that curly bit at the top, or that breaking off that curly bit won't affect the magic of the item.

But you are right, allowing someone to hit an enemy with their staff of charming isn't going to break the game.

I am more dubious about wands. Some of them have all sorts of small, intricate bits of decoration. I do rule that some of those are fragile and using them as a club has consequences.

 Wands are not staves. Nor clubs.

A magical staff can be used as a quarterstaff and thus bypass resistance or immunities to damage from nonmagical attacks. I'd also let a rod be used as a club in the same fashion, may be even stab with a thin wand using it as a dagger.

Yeah, I allow a magic rod to be used as either a club or a mace depending on the PC’s proficiencies.

The DMG actually has some guidance about this. Non-consumable magical items have resistance to all damage. They are explicitly not delicate. I dunno, trying to see whether or not a wand snaps because the player has to try to stab someone with it just seems petty and mean, as well as unsupported by the rules.

Quote from ArntItheBest >>

Quote from SagaTympana >>

The DMG actually has some guidance about this. Non-consumable magical items have resistance to all damage. They are explicitly not delicate. I dunno, trying to see whether or not a wand snaps because the player has to try to stab someone with it just seems petty and mean, as well as unsupported by the rules.

 Well then I'd at least give the wand a -7 to hit or something. Wands may be pointy, but they are not honed to an edge like a dagger and would have a VERY hard time getting through any armor or even into someones skin.

 I would make a wand a improvised weapon, so, unless you have the Tavern Brawler feat, no proficiency bonus for the attack.

Quote from Voras >>

Quote from ArntItheBest >>

Quote from SagaTympana >>

The DMG actually has some guidance about this. Non-consumable magical items have resistance to all damage. They are explicitly not delicate. I dunno, trying to see whether or not a wand snaps because the player has to try to stab someone with it just seems petty and mean, as well as unsupported by the rules.

 Well then I'd at least give the wand a -7 to hit or something. Wands may be pointy, but they are not honed to an edge like a dagger and would have a VERY hard time getting through any armor or even into someones skin.

 I would make a wand a improvised weapon, so, unless you have the Tavern Brawler feat, no proficiency bonus for the attack.

 
This. And I would also give it a negative damage modifier, something like 1d4-2 since it’s not got a point nor much mass behind it. It would really require a high Str and a good roll to do much damage with one. It would still technically work, just not very well.