I was looking at the rules for underwater combat, PHB 198, and noticed
…Even against a target within normal range, the attack has disadvantage unless the weapon is a crossbow, a net, or a weapon that is thrown like a javelin (including a spear, trident, or dart).
Now this struck me as odd because a net is a thrown weapon and could be included in the list of weapons you throw, and because a net is always used at disadvantage because it has a range of 5/15, meaning more than 5 feet away but less than 15 there's disadvantage because it's long range but within 5 feet is at disadvantage because it's a ranged attack in melee range.
The net seems a worthless thing to mention that I don't have disadvantage if it doesn't remove the disadvantage that a net normally has since per PHB 173
If circumstances cause a roll to have both advantage and disadvantage, you are considered to have neither of them, and you roll one d20. This is true even if multiple circumstances impose disadvantage and only one grants advantage or vice versa. In such a situation you have neither advantage or disadvantage.
I see this and can think that either it's a worthless bit of text (If ranged attack in melee range still applies), or that you can throw a net up to 5 feet without disadvantage (the underwater rules state, though not explicitly, that I can use a net up to it's normal range and it doesn't get disadvantage). This seems to be a case of specific beats general but I don't know which is which.
In a situation underwater with no influence other than the net and the environment affecting advantage/disadvantage does attacking a creature within 5 feet with the net have disadvantage or not?
Best Answer
About ranged attacks
Ranged weapons have a normal range and a long range. Under normal circumstances, you can attack enemies which are within your long range, but as soon as they are beyond normal range you have disadvantage on the attack. Attacking a creature while engaged in close combat does also impose disadvantage on ranged attacks. (PHB p.195)
Underwater Combat
In the special case of underwater combat, an attack beyond normal range is an automatic miss and an attack within normal range is at disadvantage unless it is one of the explicitly stated. This rule is a specific beats general case regarding ranged attacks and their two ranges.
This means, that nets are excluded from the water's specific case rule regarding attacks within normal range. So the long range is a automatic miss rule still applies to them.
The disadvantage for attacks with a net is not caused by its range, but by close combat
The rules of ranged attacks in close combat do still apply. You could still use e.g. a crossbow under water to attack a creature 10ft away from you without getting disadvantage due to the range category, but when you are engaged in close combat you still get disadvantage on ranged attacks (unless you got the crossbow expert feat) same applies for nets.