SWEENEY TODD lyric question

[morosco]

LOVETT:
Lawyer's rather nice.
TODD:
If it's for a price.
LOVETT:
Order something else, though, to follow,
Since no one should swallow it twice!

Is the lyric "since no one should swallow it twice" a joke referring to lawyers? Could someone explain the joke? This is one I don't get.

[EthelMae]

I saw the show 27 times and I always thought that lyric was, indeed, referring to lawyers and how one should never believe what a lawyer says once, much less twice. Other thoughts?

 

[morosco]

Thanks EthelMae.

I was just doing some research and found the phrase "hard pill to swallow" and one of the definitions from Cambridge Dictionary says "difficult to believe or accept". Perhaps the joke is that what a lawyer says can't always be believed and thus what they say cannot always be accepted?