In the TV series Goliath (Amazon Prime), Billy Bob Thornton plays Billy McBride, a badass but disgraced trial lawyer excommunicated from the massive firm that he founded. The show is about how Billy plots his attempt at redemption and revenge.
There's a scene in which Billy is prepping a deponent, his own witness, and conveys his five rules for depositions:
In US: must be an attorney licensed and in good standing in any state, territory or DC.
Outside US: must be a lawyer or equivalent (eg counselor, barrister, advocate, solicitor), duly educated and licensed/accredited and in good standing.
As a general rule, experienced and currently practicing lawyers, and those teaching law in the legal academy, are more likely to be admitted.