I'll bite, even though fact checking is nerd shit. Both of the claims in the image were made by Tulsi Gabbard in a primary debate in 2020 and contain factual errors but are not complete fabrications.

The 1500 figure is actually closer to the total number of people jailed by Harris for marijuana-related crimes (1,974). Statistics broken down by race, sex,and ethnicity are not available.

https://www.sfchronicle.com/politics/article/Fact-checking-the-Democratic-debate-attacks-14275081.php

It appears that Harris blocked DNA testing in the case of one Black man on death row, not two. He was, however, blatantly framed. He has also not been executed, but remains on death row. She called for officials to allow testing after she was no longer AG, after being called out by a New York Times article.

https://www.nytimes.com/interactive/2018/05/17/opinion/sunday/kevin-cooper-california-death-row.html