Upon any prosecution for procuring, offering or casting an illegal vote, the accused may give in evidence any fact tending to show that the accused honestly believed upon good reason that the vote complained of was a lawful one.
19 Del. Laws, c. 39, § 52; Code 1915, § 1809; Code 1935, § 1898; 15 Del. C. 1953, § 5104; 70 Del. Laws, c. 186, § 1.