At least 13 Biden campaign staff members posted on Twitter on Friday and Saturday that they made donations to the Minnesota Freedom Fund, which opposes the practice of cash bail, or making people pay to avoid pre-trial imprisonment. The group uses donations to pay bail fees in Minneapolis.

Biden campaign spokesman Andrew Bates said in a statement to Reuters that the former vice president opposes the institution of cash bail as a “modern day debtors prison.”

But the campaign declined to answer questions on whether the donations were coordinated within the campaign, underscoring the politically thorny nature of the sometimes violent protests.

Bates instead pointed to Biden’s comments that protesters have the right to be angry but that more violence won’t solve justice problems.