GST (Goods and Services Tax) has several measures in place to catch tax evaders and prevent tax evasion. Some of the ways in which GST catches tax evaders are:

GST registration: Every business with a turnover exceeding the threshold limit of Rs. 20 lakhs (Rs. 10 lakhs for North-Eastern and hill states) is required to register for GST. The GST registration process requires businesses to provide accurate details of their business operations, including details of their suppliers and customers.

Electronic invoicing: GST has implemented electronic invoicing to create a digital trail of transactions. All invoices are required to be uploaded to the GST portal, providing authorities with an accurate record of transactions.

Input tax credit (ITC) matching: GST authorities match the ITC claimed by businesses with the ITC claimed by their suppliers. This helps to identify any discrepancies or mismatches in ITC claims.

Data analytics: GST authorities use data analytics to identify businesses that are underreporting their turnover or claiming excess ITC. Data analytics is also used to identify businesses that have not filed returns or have filed incorrect returns.

Reverse charge mechanism: Under the reverse charge mechanism, the liability to pay GST is shifted from the supplier to the recipient. This mechanism helps to identify businesses that are not registered under GST.

GST audits: GST authorities conduct audits to ensure compliance with GST regulations. GST audits help to identify businesses that are not complying with GST regulations.

Overall, the implementation of GST has created a digital trail of transactions, making it easier for authorities to catch tax evaders and prevent tax evasion.