USC announced their official practice admittance policy:

Admittance to USC football team practices on campus will be restricted to pre-approved guests who submit requests 24 hours in advance, according to a policy released today by the USC athletic department. Those eligible to attend practices if pre-approved are parents, guardians, spouses and siblings of current players, as well as a limited number of guests escorted by certain USC administrators. Additional limited exceptions (such as other relatives of players) may be made with the pre-authorization of a Senior Associate Athletic Director. Those who are pre-authorized to attend practices may only have contact with coaches and athletic department personnel. Among those not permitted access to practice are agents (such as athlete...

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