What, if any, Code breaking legal ramifications would there be for a Tytalus who used the Persona Supernatural ability on their own coven mates?
If they use no magic at all, keeping the Persona strictly Supernatural ability and mundane disguises, would their intrusion into the sanctums of other magi, their spying on other magi, and all around horrible dishonorable actions be an actual crime?
A Tytalan mage assumes his Persona, and using relatively mundane methods enters the sanctum of another Hermetic mage, Secondus.
Secondus discovers this apparent mundane person, and being the wrathful sort, attempts to slay him/capture him/turn him to a toad. When this does not work as expected, due to Parma, Secondus concludes that this is a
A) Faerie, on some fae mission. He can legitimately slay said faerie. This is not molestation - the faerie entered a place clearly marked and set aside, and has violated these boundaries.
B) Demon, and must be destroyed immediately, and not talked with.
C) Mage, who in entering the Sanctum has forfeited immunity, and can be legitimately slain under the Code.
D) Hostile non-Hermetic magician, who is clearly an enemy - why else would he be invading a Sanctum? - and should be captured and interrogated or destroyed, or both in that order.
and also not
E) An Angel, as they generally are wise enough to appear to magi in a more clearly Divine mantle.
Outside of a sanctum, a Tytalus mage caught spying under your circumstances may not be considered scrying (although the Heartbeast ruling could easily apply), but he might well be expelled from the Covenant, which can often have serious legal repercussions, and/or might even be fined by the Covenant, depending on the gaggle of magi in question.
Persona is magic, even if the magic is momentary. The code does not differentiate between Hermetic and Non-Hermetic magic. The very use of Persona in the act of breaking into someone's sanctum (or indeed, prying into their affairs in any way) would be construed as scrying. Previous examples have shown that scrying is taken very seriously - probably because it's difficult to prove. And I think the most difficult to prove cases of scrying would draw the harshest punishments (because you knew you were breaking the code and took great pains to cover your tracks, which proves premeditation and lack of remorse).
Just to chime in: magic is magic. If a magi uses magic as part of a process to directly observe another magi, then it's scrying - regardless of whether or not they intended to do so. And I'll agree that most tribunals take the strictest letter of the law when it comes to scrying - being invisible counts, as does the aforementioned Heartbeast ruling.
However - like most things in the Hermetic Code, the punishment tends to be based on consequences. If you don't actually learn anything secret from your scrying, then it's not a big deal: that's the Lineage of Praxis ruling. ("If the only thing you learn from your scrying is that a maga does, in fact, have the Gift, then we aren't going to punish you.") But that's a pretty narrow ruling, and doesn't actually deny the fact that it's scrying. Similarly, that's why it's not illegal for shapeshifted magi to sit at the dinner table with their soldales - the only thing they're learning from their "scrying" is that the magi are sitting around the table with them. Further, everyone at the table seems to be aware of the shapeshifted magi's state, and is fine with it - thus (likely) giving implied consent to the "scrying". In contrast, if the magi were hiding under the table in their mouse heartbeast form, listening in on a mystery cult's inner secret? Yeah, that's certainly punishable.
Further, just walking around the covenant in a Persona would count as scrying, if the Tytalus perceives a maga while doing so. But again, it's what they LEARN that makes it a punishable crime - if the only thing they see is the target magus walking around, it's a good bet that the Tribunal won't care. If the tytalus sees another magi in an illicit affair with someone's apprentice...well, OK then. That's certainly punishable as scrying.