Email spoofing is simply a term for "faking" the FROM address of an email message. If a message has a from address of SOMEONE@LACA.ORG, then that message SHOULD come from a LACA-owned email server.
However, this is not always the case.
Spammers will insert fake FROM addresses into messages to make it LOOK like they came from LACA, but they did not.
Sometimes, there ARE legitimate reasons to spoof an email. Some districts use mass mailing services like Constant Contact, and some alert systems that send out school closing announcements will using spoofing to make the notice looks like it comes from your school district.
LACA tags all emails that are spoofed, to let you know if it truly came from LACA's email system or not.
Not all tagged messages are bad, but exercise caution viewing attachments or responding to messages that
are spoofed, as there is a much higher chance that they are NOT legitimate than other messages.