1) It is strange to hear from you the position of "we don't have proof it's dangerous, therefore we should treat it as safe". This was written by a magic user in at least some sort of code. This is sensitive information. It wouldn't surprise me if there was stuff like demon summoning was in there, or at least stuff related to demons - as a magic using priest, Father Murphy would likely have dealt with real exorcisms in his life. Even if there's not demonic or fae lore in there (ie you can't use it to summon something), and there are no sensitive secrets, like location and nature of Demonreach, this should be checked first.
2) This is hilariously wrong. Write them a note. We can have the identity set up well before they can check it. Our abilities to forge an identity outpace their abilities to check it. We can say that Lieutenant Murphy is going to be checking that we aren't absconding with the books. It's not a problem.
What would they be asking for, anyway? At worst, if they ask for ID, we say "sorry, don't have it on me, can I come back in the evening? I'll have all the credentials with me then.", and come back in the evening with foolproof identity.
1) Someone as young as Harry Dresden had designated successors for his stuff in the event of his death.
If the late Father thought it was necessary to put down shit to writing, he's demonstrably competent enough to have asked someone to pick up or dispose of his journal and any other stuff if he thought it was critically important.
Or written a will. He had local family who would carry out instructions, as well as people in the clergy.
So my inclination is to assume that there is nothing critical there right now. Until we check.
If they knew who we were, or were sufficiently in the know, Molly Carpenter, Chicago local and daughter of Michael Carpenter might ask them to hand it over for a couple days.
Just as a precaution.
But Maggie Smith, out of state PhD student from St Louis, MO, has no standing to ask any such thing.
And doing so would attract the sort of scrutiny we cant afford for a paper-thin cover identity.
2) Go home and actually commit state and federal crimes of forgery and identity theft while dealing with cops.
This is a police family. Mama Murphy's husband made it to Captain in the CPD before his "suicide".
There are multiple cops here right now, as well as an FBI agent.
If Rick Broughton or Sam Murphy calls up the St Louis FBI Office or St Louis Police Dept and asks a friend to have an agent to drop by and talk to the professor we claim to be doing our PhD under, then what?
This isnt the 19th century any longer.
You are stumbling into the classic "old woman who swallowed a fly, and then swallowed a spider to catch the fly etc" doom spiral with telling lies.
Thats why smart people generally make as few hard statements when deceiving people as possible.
I will reiterate: Molly could have walked in here with her own face and been good. She had committed no crimes, just doing research. We voted to complicate this entire encounter with cover identities and false faces and obvious magic where they werent necessary.
And now you are suggesting we commit actual interstate federal crimes of impersonation and identity theft.
In front of multiple police witnesses, a police widow, and a priest.
Everything you are suggesting now are putting Molly, and both Father Forthill and Murphy herself, in legal jeopardy.
Karrin Murphy is a COP.
Dont just assume that her ethics are infinitely flexible. HARRY doesnt do that, and they have more history than we do.