Securing access to group accounts on a computer system

A computer-implemented method, comprising:

• obtaining, from a smart card reader, a first digital certificate stored on a first smart card;
• obtaining, via a first user interface, a first PIN;
• verifying that the first digital certificate and the first PIN correspond to a first authorized user of a plurality of authorized users of a tactical application on a tactical computing system, wherein a shared account associated with the plurality of authorized users has been logged into on the tactical computing system;
• and
• displaying a second user interface that enables the first authorized user to access the tactical application.

A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a processor, configure the processor to perform operations including:

• determining that a first storage device is in communication with the processor;
• determining, based at least in part on a digital certificate stored on the first storage device and information received from a first user, that the first user is authorized to access a tactical application associated with a shared account on a tactical computing system, wherein the shared account is associated with a plurality of authorized users, and wherein the shared account has been logged into on the tactical computing system;
• causing display of a first user interface that enables access to the tactical application;
• determining that the first storage device is no longer in communication with the processor;
• and
• in response to determining that the first storage device is no longer in communication with the processor, causing the first user interface to no longer be displayed.