They did the initial interrogation in this 'controlled environment'... in the police interrogation room. There is no reason to keep on questioning them in that environment unless they have sufficient evidence to support their suspicion that one or both of them is guilty of a crime. Any new questions that arise can be handled in the living room of wherever they are staying WITH their attorney present.
LE is trying to sway public opinion, which will help their case if it ever goes to court. By insisting that the parents are not 'cooperating'... which in cop speak means they aren't giving them the answers they want... and by insisting that they come down to the station for more questioning instead of sitting down with them in their home only serves one purpose, and that is to intimidate them and to convince the public that they have something to hide.
Maybe they do... I don't know. I'm just saying that once the parents of a missing child have given LE everything they know, and there is nothing else they can possibly say that would help, there is no legal reason to keep treating them like suspects unless they have evidence to point to them as being guilty. And I hope to heck that they have more than one hit by one dog in the bedroom, because that alone would not sway a judge to sign an arrest warrant. JMO.
Putting aside, for the moment, what "unrestricted" means and what level of cooperation is being given by the parents, we know straight from Captn Young's mouth that LE needs more info about who was coming and going from the house that night. Very big and important piece of information when a baby has been taken. Right? So, at first, I think the story was that Debbi was at home with the kids, normal Monday night except dad was working, and she checked Lisa at 10:30 after earlier bathing and changing her and giving her a binky. Presumably, she then went to sleep only to be awakened by Jeremy to find Lisa missing. No holes, parents cooperating.
As questioning continued (and perhaps as a result of some LDT questions), it is determined that there are the "gaps and inconsistencies" that Debbi admitted she couldn't fill in days before she did the morning interviews about her drunkeness; the point at which the parents stopped official LE interviews conducted at the station. We now know that Debbi actually left the baby unchecked for at least 9 hours. We now know that at least a neighbor was at the house drinking with Debbi. We now know that Debbi feels she might have blacked out. Whole new ball game. We know that statistically the perp is a family member or someone who knows the family in some way.
Now, LE REALLY needs to know what happened during those gaps, maybe somebody was there and left with the baby! But, the parents aren't answering to LE's satisfaction about the comings and goings that night/morning. Why? Debbi and Jeremy are acutely aware of the fact that Jersey, Megan, and Mr. Brando have been interviewed multiple times. They know LE is looking at other people. Why then are they not down at the station answering questions and letting LE help Debbi to possibly remember details - LE may have gathered info that could spur her recollection during the course of their interviews and investiation. How do the parents know that LE doesn't have information that might help them determine that one of these folks (or others that are on the LE radar whom we haven't heard about) was involved? Sure, the parents may be anwering some questions about possible leads, but if they are not open to LE and aren't working to clear themselves, LE can't show them everything they have. I can't reconcile why these parents aren't grasping at every lead and offering themselves up to aid in the investigation like their baby's life depends upon it (because it does). They have to know that at least these 3 folks have been questioned hard, it's been all over the press.
This leads me to fear that the parents know what happened to Lisa. If they know what didn't happen or who isn't involved (which appears to be the case to me by their continued lack of full cooperation after knowing for a fact that they are not the only people being looked at by LE), then they must know what did happen, imo. If they did not know, they would want to tell LE everything about that night/morning in desperate desire to help LE put the pieces together and lead them to the perp that leads them to Lisa. Imo, they would be open to LE under any conditions upon hearing about LE investigating other possible perps (unless those possible perps are connected to the disappearance through the parents). Imo, they would take themselves and their lawyer in for questioning immediately, letting their lawyer know that they want to answer all questions and that he is only there to witness and protect them if they feel LE is being abusive.
JMO, MOO, JMHO...