Question: I've been reading many opinions from the United State Supreme Court and discovered the phrase "inter alia," meaning "among other things." I have not encountered this phrase outside of these opinions.

Is the phrase "inter alia" primarily localized to legalese? Or would it be acceptable to use it in general writing?

Answer: 
The best course, undoubtedly, is to use "among others", a phrase that can refer to people or things. 

It should be noted that "inter alia" is Latin for "among others" when "others" are things. If the others are persons, "alia" must be changed to "alios" (the OED quotes, from 1670, *The lords produce **inter alios** John Duke of Lancaster*); but when persons are meant, it is much better nowadays to use English.

Reference: A Dictionary of Modern American Usage, *B.A. Garner*, A Dictionary of Modern American Usage, *H.W. Fowler*.
*Inter alia* looks as though it can bear its weight in business reporting and used as a throw-away phrase elsewhere, usually unitalicized. It seems to be a regular journalistic condiment at the *Financial Times*. 

> 
> “...it has become increasing clear to us that top leadership had
>  shaped a culture that lacks, ***inter alia***, accountabiltly, transparency,
>  and stock ownership,” Mr. Biglari said in letter to shareholders,
>  which was filed this month with regulators. *Cracker Barrel Adopts
>  Poison Pill*, NYT Sep 23, 2011
> 
> 
> But there's more to the story, which involves **inter alia** speculating
>  monks, unusual lending practices and a man called Andreas Vgenopoulos.
>  *Cyprus Popular Bank: ‘Money is gone (allegedly)*, FT Jun, 15, 2012
> 
> 
> Boston is famous – **inter alia** I suppose – for tea parties, beans and a symphony orchestra. No one, however, talks about its coffee. Nor
>  for that matter, talks too much about its ballet comparny ... *Ballet:
>  Bostonians in New York Debut at Hunter*, Clive Barnes NYT Oct 22, 1967
> 
> 
> ... Jane Jacobs, a
>  grand strategist of the Broome Street rebellion, whose triumph
>  launched the age of neighborhood preservation and rehabilitation and
>  with them the celebration of craftsmanship that helped make downtown
>  Manhattan a world center of style and, **inter alia**, a culinary
>  Parnassus. *Food; Way Uptown*, Jason Epstein, NYT Apr 11, 2004
> 
> 
> Mixed alliums in a chilled pine fusion contained, **inter alia**, a cold
>  consommé of such purity and balance that I’m still trying, hours
>  later, to tell if it was sweet, savoury, simple or complex. *Daddous,
>  London*, Tim Hayward FT Jun 8, 2012
> 
> 
> Murder abounds in Leos Carax’s *Holy Motors*... Its Borgesian and
>  bewitching fable of changing identity – Denis Lavant chauffered around
>  Paris becoming, ***inter alia***, a street beggar, leprechaun, millionaire
>  businessman and hitman – has interludes for a Kylie Minogue production
>  number and a riot of digitised monsters. Nigel Andrews, FT May 26, 2012
> 
> 
>