Developing C# webservice code without a valid cert

Is it possible to use the Tridion Docs WCF functions if your server does not have a valid cert? I am running the basic code seen at the link below but it throws an exception about trusting the server. The server does not have a valid certificate.

https://docs.sdl.com/806356/347098/sdl-tridion-docs-14-sp3/best-practices-using--svc-web-service-in-c-