Besides that it violates Heller SCOTUS ruling (?) about needing to keep a firearm locked.
Write how this personally would affect you. Any violation would take away your 2a right in hawaii for 20 years due to the other law being past 2 years ago.
This law is a copy of laws from other states. Do a few searches to see what the other opponents said.
Constitutionally, there's been no ruling on forcing the use of trigger locks, lock boxes or gun safes to store firearms.
The biggest argument against is enforcement. The only way this law can be enforced is after someone gets a gun they shouldn't have had access to and does something illegal with it. the alternative would be to force gun owners to allow home inspections by las enforcement to ensure storage law compliance.
So, if there's a storage law, not only would the person who took your gun be prosecuted (if still alive), the state could also prosecute you as the gun owner who obviously did nothing wrong with your gun. They are looking to blame someone for the damages caused by guns, and a dead shooter is difficult to punish. Most gun deaths are suicides, so the number of suicides using someone else's gun would also be high.
If you notice the alterations in the bill, they are changing from a stance of forcing anyone with minors in the home to lock up their guns. Whether or not the minor is a resident or just a frequent visitor, the owner must lock it up if there is a reasonable chance of a minor getting possession of it. They are now wanting to make the statute apply to anyone regardless of the risk of a minor gaining access.
it's been my contention forever that if the the state wants to force us to buy safe storage for our guns, they need to help subsidize it. Offer rebates for first time gun owners to buy a lockbox or safe. When someone needs a gun, the cost of the firearm, ammo, accessories, training (including private range time), permits, and carry licenses are very expensive. Adding a mandatory locking storage is just additional cost. The more the state forces gun owners to spend, the more the "right to keep and bear arms" becomes a right only the upper classes can afford to exercise. People living where they may actually need protection won't be able to afford to do so. And someone buying a gun in a poor area isn't going to be forced into buying a safe -- at least not right away. They will put that off until they can save for it which may be too late to stop what the bill is intended to stop.
in short, if the state wants every gun owner to lock their guns up at home, they need to shift the burden of that cost to the state. We already pay fees for "gun violence prevention." Use some of that to enact these programs rather than making more laws to punish gun owners with no way to effectively enforce them.