Personally, I'd argue Police and Intel IDs be limited to Cruisers, with a specific exemption towards Battlecruisers as they shouldn't have those (outside of maybe SRPs and Official Faction perks).
The way I'd always viewed Police in Freelancer as per Vanilla is that they actually make up the bulk of the Security of a House. The Navy on the other hand, they're the heavy lifters, applied by the state to put what limited heavy firepower the House has on hand in specific locations and designed to bolster Security forces, reinforcing positions against militant groups where necessary. They exist to fight the enemies of the state.
In Discovery however, we have this problem of all Navies being excessively bloated since Vanilla coupled with both the fact that many unlawful factions now also have hefty Military might and that it's a space game, our head canon says Military ship should be able to stop lawbreaker, especially when there's no police around to do so (player pop issue).
My personal take on it, would be that Military IDs have the ability to enforce laws at the edges of House Space or in specific flashpoint locations where their presence is specifically allocated by the state, while Police should be able to enforce them throughout the entire House and have dope perks to enable it.
Intel IDs shouldn't be general law enforcement, this I agree. However, it could be argued that they should still have some ability to enforce the law when required (FBI case in point). It would strictly all depend on the House to be honest and how their Intelligence Agency theoretically operates.
When contending with a monster, you'd be wise to give the devil his due.
