You won't see a sealed record. There are many companies you can find on-line. The Office of Court Administration lets you do a check for New York by name and date of birth but it does not pick up any aliases and I don't think you can ask a potential employee for his or her date of birth. There are companies that do the checks by fingerprints.
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There are a lot of companies in this area who will do these background / criminal conviction checks for you on an as needed basis. The costs are probably cheaper than you think and it is worth speaking to a couple of different companies so you can get a handle on their services.
As you are aware the hiring of employees is one of the most difficult decisions that you can make. You want to take great care about who you hire to run your business. Running a background / criminal conviction check is a great first start in vetting your potential employees.
Many private investigative firms will perform background checks for a fee. Oftentimes they will agree to look further than simply criminal records, and they will also perform media checks and other searches.
There are private companies that can conduct background checks, although you will not likely have access to any sealed records.
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