The impact of social media cannot be denied. The 2009 word of the year was “tweet,” and the word of the decade was “google,” according to the American Dialect Society. Social media such as Twitter, Facebook, MySpace, Flickr, and YouTube—which are defined by their user-generated content—have wiggled their way into most people’s working hours, and thus onto many workplace computers.

In the field of Human Resources, most talk of social media has to do with pre-employment: talent sourcing, advertising job openings, and performing background checks. But social media is now integrated with each stage of the employee lifecycle: before, during, and after. HR practitioners should study their proper use (and possible misuse), and learn what steps to take now to maximize their benefit while heading off potential legal problems. An excellent article on this topic was just published in The National Law Journal. In “Social media permeate the employment life cycle: Employers must address their use and misuse before, during and after an employee's tenure,” labor and employment attorney Renee M. Jackson writes about the simultaneous opportunities and risk presented by social media. Here are some of her top thoughts, as well as those of HR pros, on points you should consider at each stage of the employee lifecycle. PRE-EMPLOYMENT

The networking power of social media is undeniably helping people find jobs, and helping companies find talent. If you’re ready to take full advantage of it, check out an article like Fistful of HR’s “5 Must-Use Social Media Tools For HR & Recruiting Professionals In 2009.”

Know this, though: because people now publicly disclose much more information than they did in the past, organizations must take care, writes Jackson in The National Law Journal:

… Applicants may reveal more information about themselves through social media than they normally would during the hiring process. In making hiring decisions, employers can lawfully use information relating to an applicant's illegal drug use, poor work ethic, poor writing or communications skills, feelings about previous employers and racist or other discriminatory tendencies. Employers may also lawfully consider an applicant's general poor judgment in maintenance of his or her public online persona. Employers, however, may face liability under federal, state and local law for using any information learned from social media about an applicant's protected class status — race, age, disability, religion, sexual orientation, etc. — in a hiring decision. It may be hard for the employer to prove in later litigation that it only viewed, but didn't actually use, the information obtained in a social medium when making its hiring decision.

Your organization must seriously consider whether you want to use social media in your talent searches at all. If you do, Jackson recommends that you follow these guidelines:

• Conduct uniform searches that are just and consistent
• Use a non-biased third party to perform social media research
• Do not "friend" applicants to gain access to non-public information
• And other important points

DURING EMPLOYMENT

One of the biggest issues caused by social media during an employee tenure is the simple theft of working time. There are also matters of privacy, nondisclosure, taboo topics and hostile work environment, brand protection, and many more. The good news is, this is the stage when you have the most control over the situation. Most organizations would benefit from a well-researched, clear, and fairly applied social media policy. To research the matter, I recommend  beginning with “10 Must-Haves for Your Social Media Policy” by Sharlyn Lauby, who you may know as The HR Bartender, or "How to Develop a Social Media Policy" from About.com. There are a wide range of policies, but one thing all the experts agree on is that a successful policy is not arbitrary, but is a genuine expression of the needs of an organization which has considered both the risks and rewards of this new media.

Some of Jackson's top recommendations for points to include in a policy are:

• A prohibition on disclosure of the employer's confidential, trade secret or proprietary information
• A request that employees keep company logos or trademarks off their blogs and profiles and not mention the company in commentary, unless for business purposes
• An instruction that employees not post or blog during business hours, unless for business purposes
• A request that employees bring work-related complaints to human resources before blogging or posting about such complaints
• And others

AFTER EMPLOYMENT

Then, there are the former employees. Some will be nice, and some will be not-so-nice.

The best defense against nightmare scenarios like this and like this is a having had a good social media policy in the first place—one that lasts beyond employment, if at all possible. But if you are dealing with a situation that falls outside of that, you might want to read an article such as “Dealing with Disgruntled Ex-employees via Social Media.”

Another huge issue is recommendations. Increasingly, people are asking former colleagues to write them recommendations on social media such as LinkedIn. Is that the same as an official post-employment recommendation? Jackson says yes—although it's difficult to define when people are speaking for themselves, and when they are speaking on behalf of the organization. It's a good reason to have a solid policy in place.

The warmest and fuzziest scenario is positive relations through social media in the form of corporate alumni networks. In Computer World's article, "The new word for tech's ex-employees is 'alum'" large, successful sites catering to groups of ex-employees are examined. Microsoft's alumni network, for example, has 10,000 members—what an incredible opportunity for networking and goodwill!

THE TAKEAWAY What HR should take away from this, writes Jackson, is that the risks of social media are too great to be ignored any longer.

First, employers must understand the myriad issues surrounding social media in the workplace in order to strike the appropriate balance in the eyes of their employees and the law. Then, employers must craft appropriate policies and procedures regarding social media that are consistent with their industry and firm culture, and apply such policies in a consistent, objective and nondiscriminatory way.

Workers are tweeting, googling, and friending, and they're doing it at all stages of employment. We need to acknowledge this, and craft good policies in response.