Government agencies collect a huge amount of data that they make available online for free.
When searching for data and statistics, add "site:.gov" to your keyword search in Google to limit to government sites.
Also, figure out the agency that would collect statistics for your topic and search directly on their site.
Add "site:.org" to your keyword search in Google to limit to organizational web sites.
For example, the search "death penalty" site:.org, brings back:
Remember to evaluate websites for their accuracy, currency, and credibility. Please ask if you are unsure about a website.
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