There have been a number of plays by this name over the years.

Including:

Honesty the Best Policy, a two act farce featuring a bookseller, a naturalist, a poet, and a middle aged man, written by an anonymous author, and printed in 1791, but censored and withdrawn from performance.

Honesty the Best Policy by Mark Lemon (1800)

Honesty is the best policy, or, True to the core, a play in one act and one scene by John Maguire, published in New York by C.T. De Witt, 1877.

Those performed in South Africa are:

Honesty the Best Policy by Mark Lemon (1800)

This is a drama in two acts by Mark Lemon (1809-1870)[1].

The original text

Described as "adapted to the English stage", from a French text (possibly L'Honnête Homme, ou Le Rival Généreux, a 1789 three act comedy by Dumaniant), it was first performed in and was published in 1800 by Davidson in London.

Performance history in South Africa

1854: Originally scheduled for production on 5 June 1854, and finally performed (as Honesty is the Best Policy) in Cape Town's Garrison Theatre by the Garrison Players on 18 September 1854 as part of a benefit performance for the comedian Mr Kirton, along with The Spitalfields Weaver (Bayly) and Middle Temple (Peake).