Wow, ok, there is so much misinformation in this thread...
Background: I specialize in partisan political tech consulting - primarily hired by start ups in the political tech space and VC's that are either evaluating a company in this market or have already invested and need a "subject matter expert" to make sure no one messes up too badly. This is a problem that I talk to firms and starts up about a lot (like three+ times this week).
> Is it legal not accept their business/shut down their account?
Yes. As long as they are not a protected class AND the reason you are doing so is outlined in your terms of service. Even if they are a protected class there are some exceptions but leave that to your lawyers.
> By denying this group, are you locking out 50% of your market?
Absolutely not. While in theory saying "my company only sells to Democrats" could be a bad idea if your product had market fit outside the political market, saying "we do not sell to Republicans" will potentially grow your market share in politics. Political organizations frequently do not spend money with vendors that also sell to their opponents.
If you are targeting the political market it is often important (if not required) to 'pick a side' at the beginning. There has never been a successful nonpartisan politically focused tech company in the US, ever. NationBuilder for example has been a complete financial failure while other companies like Polis are nonpartisan but their primary market fit is nonpolitical.
> What about Microsoft, Firefox, Stripe, or Eventbrite? They will sell to anyone!
Yes and no. Stripe turned off service for the hate site Gab.com. Additionally there is a major difference between a platform (Microsoft Word) and a vital tool for winning in the political space (like a voterfile), especially in the already fairly saturated US market - internationally it's a little different, but that's really just because there are less options.
Are you a platform or a tool? Companies like Hustle have tried really hard to fall into that "platform" category but between their clients seeing them as a tool and saturation of their niche (p2p SMS services) they decided to not sell to Republicans. If they had not made this choice their Dem clients would have left.
> What should you do / how have other companies dealt with this?
Assuming you are not a strictly politically focused company (which I'm guessing you're not, otherwise this would have come up earlier) the best thing to do is work with your team to come up with a terms of service that reflects your values.
A good example of this is saying "we do not allow clients to use our tools to promote violence, hate speech, or fake news through this system." I can't tell you the number of times I've gotten on the phone with some client's lawyer and they want to know what we actually define as hate speech, to which my response usually is "if you have to ask..."
Eventbrite serves both Dems and Republicans, they even have seperate staff to work with each party! That being said, NGP VAN only works with Dems and i360 only works with Republicans. Which one are you more similar to?
> Is it bad that your employees have opinions on how what they build should be use?
Happens to everyone and should be celebrated, not shut down.
https://www.theverge.com/2018/11/28/18116447/google-employee...
https://www.theguardian.com/technology/2016/feb/22/tim-cook-...
https://www.theverge.com/2018/3/30/17179100/facebook-memo-le...