...Imperial government begins at the subsector level. ...
Wouldn't it be considered to begin at the starport level, that being Imperial territory?
There is a different thing between the civil matter of defaulting on a loan, and the criminal matter of hiding collateral. The latter is essentially stealing, and police get involved in my experience as a criminal defense attorney. Usually, if the vehicle is hidden, and the lender can show that it is being hidden, then the police will go ahead and put a warrant out. ...
For theft? Beg pardon, but whether or not it's considered theft - or whatever other statute the police are relying on for their warrant - depends on the precise wording of state law, which of course will vary from state to state, which makes that a difficult precedent to apply to the present discussion. Establishes only that it's possible, and given that canon doesn't provide many details, almost anything is possible. Considering the forum we're in, even canon is not a limit and literally anything is possible.
Which brings me to a point: we're having a great discussion, but a lot of it's argument about how the Imperium would or wouldn't do something when there's only a little canon information on what the Imperium would actually do. Given gaps in canon that you could fly a skipped ship through, almost anything is possible, and the flexibility handed the game master under CT Book 2 means you can have anything from a universe that makes skipping nearly impossible to one where - abetted by an apathetic Imperial government - it's a serious problem.
My answer, as I stated in the opening post, was carrot-and-stick. The debtor has a 20% starting stake, more as time goes by. Sure, a creditor can make rules that take all of that on a default, but it's counterproductive: you increase the odds of a skip, and if you contrive to make laws that make skipping impossible, then you decrease the demand for your loans - I'm not about to sink 7+ million into a high-risk venture with a potential for 100% loss when I can make safer investments planetside.
To replicate circumstances that favor the kind of active tramp shipping sector that Traveller shows us, you need circumstances that encourage folk to risk that 20%, and - in my opinion - that is best had by creating circumstances that allow them to recover a reasonable chunk of that investment if the business goes sour. That way, they don't have an incentive to skip: if the business fails, the bank gets the ship and a nice profit from fees and penalties carved out of that 20%, the captain/owner walks away with the surviving portion of that 7+ million to try to grow into his next venture (or retire on), and the bank looks on the potential for the captain/owner to come back in a few years and try it again. If he skips, he risks millions on the hope that he can somehow stay ahead of the bounty hunters a.k.a. skip tracers.
That has several advantages. It favors players: the bank has a profit incentive to bargain with a player if he can't make a payment, to extend the player a bit more rope (for a suitable fee) to either pull himself out of the hole or hang himself with. It gives the game master some wiggle room when the players show up in port a bit short for the next payment (and an opportunity to confront them with corrupt bankers who want a little something extra to provide the service). It creates a distinction between being behind on payments (with the bank's consent) and skipping. If it comes to foreclosure, the player's grounded with enough of a stake to have a realistic hope of growing it into another ship one day, which offers a direction for continued campaigning. It makes skipping rare - only the die-hard who will not accept the inevitable gambles his remaining wealth that way - which offers an excuse for an apathetic Imperial government that leaves the skip-hunting primarily in the hands of the creditor. Also makes skipping more an interesting campaign possibility than a certain-doom event, since the players stand a better chance against pursuing skip-tracers and the odd (and bribable) local official than against the gathered might of the Imperium.
After all, it's ultimately about crafting an interesting adventure, no?
Here's an interesting bit: some auto-loan creditors are now installing an interlock device that prevents your car from starting if you fall behind in payments. I'm not sure how that works; it was mentioned on a Federal Trade Commission consumer website, but no details were given. I'm guessing it responds to a signal sent by the creditor, or maybe they give you a code to enter every time you make a payment - and you don't get a code when you miss a payment. Of course, the average Traveller ship captain's more savvy about how to get around such things than the typical Terran fry cook who might buy a car from an operation that uses such things.